Implement blur-hash based low resolution thumbnail previews.

build.gradle

@@ -96,7 +96,7 @@ dependencies {
     implementation 'org.conscrypt:conscrypt-android:2.0.0'
     implementation 'org.signal:aesgcmprovider:0.0.3'
 
-    implementation 'org.whispersystems:signal-service-android:2.13.8'
+    implementation 'org.whispersystems:signal-service-android:2.13.9'
 
     implementation 'org.signal:ringrtc-android:0.1.4'
 

res/layout/thumbnail_view.xml

@@ -4,6 +4,16 @@
     xmlns:tools="http://schemas.android.com/tools"
     xmlns:app="http://schemas.android.com/apk/res-auto">
 
+    <ImageView
+        android:id="@+id/thumbnail_blurhash"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:adjustViewBounds="true"
+        android:clickable="false"
+        android:longClickable="false"
+        android:scaleType="fitCenter"
+        android:contentDescription="@string/conversation_item__mms_image_description" />
+
     <ImageView
         android:id="@+id/thumbnail_image"
         android:layout_width="match_parent"

src/org/thoughtcrime/securesms/attachments/Attachment.java

@@ -4,6 +4,7 @@ import android.net.Uri;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.stickers.StickerLocator;
 
@@ -44,10 +45,14 @@ public abstract class Attachment {
   @Nullable
   private final StickerLocator stickerLocator;
 
+  @Nullable
+  private final BlurHash blurHash;
+
   public Attachment(@NonNull String contentType, int transferState, long size, @Nullable String fileName,
                     @Nullable String location, @Nullable String key, @Nullable String relay,
                     @Nullable byte[] digest, @Nullable String fastPreflightId, boolean voiceNote,
-                    int width, int height, boolean quote, @Nullable String caption, @Nullable StickerLocator stickerLocator)
+                    int width, int height, boolean quote, @Nullable String caption, @Nullable StickerLocator stickerLocator,
+                    @Nullable BlurHash blurHash)
   {
     this.contentType     = contentType;
     this.transferState   = transferState;
@@ -64,6 +69,7 @@ public abstract class Attachment {
     this.quote           = quote;
     this.stickerLocator  = stickerLocator;
     this.caption         = caption;
+    this.blurHash        = blurHash;
   }
 
   @Nullable
@@ -144,6 +150,10 @@ public abstract class Attachment {
     return stickerLocator;
   }
 
+  public @Nullable BlurHash getBlurHash() {
+    return blurHash;
+  }
+
   public @Nullable String getCaption() {
     return caption;
   }

src/org/thoughtcrime/securesms/attachments/DatabaseAttachment.java

@@ -1,8 +1,11 @@
 package org.thoughtcrime.securesms.attachments;
 
 import android.net.Uri;
+
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.mms.PartAuthority;
 import org.thoughtcrime.securesms.stickers.StickerLocator;
 
@@ -19,9 +22,9 @@ public class DatabaseAttachment extends Attachment {
                             String fileName, String location, String key, String relay,
                             byte[] digest, String fastPreflightId, boolean voiceNote,
                             int width, int height, boolean quote, @Nullable String caption,
-                            @Nullable StickerLocator stickerLocator)
+                            @Nullable StickerLocator stickerLocator, @Nullable BlurHash blurHash)
   {
-    super(contentType, transferProgress, size, fileName, location, key, relay, digest, fastPreflightId, voiceNote, width, height, quote, caption, stickerLocator);
+    super(contentType, transferProgress, size, fileName, location, key, relay, digest, fastPreflightId, voiceNote, width, height, quote, caption, stickerLocator, blurHash);
     this.attachmentId = attachmentId;
     this.hasData      = hasData;
     this.hasThumbnail = hasThumbnail;

src/org/thoughtcrime/securesms/attachments/MmsNotificationAttachment.java

@@ -10,7 +10,7 @@ import org.thoughtcrime.securesms.database.MmsDatabase;
 public class MmsNotificationAttachment extends Attachment {
 
   public MmsNotificationAttachment(int status, long size) {
-    super("application/mms", getTransferStateFromStatus(status), size, null, null, null, null, null, null, false, 0, 0, false, null, null);
+    super("application/mms", getTransferStateFromStatus(status), size, null, null, null, null, null, null, false, 0, 0, false, null, null, null);
   }
 
   @Nullable

src/org/thoughtcrime/securesms/attachments/PointerAttachment.java

@@ -4,6 +4,7 @@ import android.net.Uri;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.stickers.StickerLocator;
 import org.thoughtcrime.securesms.util.Base64;
@@ -20,9 +21,10 @@ public class PointerAttachment extends Attachment {
                             @Nullable String fileName,  @NonNull String location,
                             @Nullable String key, @Nullable String relay,
                             @Nullable byte[] digest, @Nullable String fastPreflightId, boolean voiceNote,
-                            int width, int height, @Nullable String caption, @Nullable StickerLocator stickerLocator)
+                            int width, int height, @Nullable String caption, @Nullable StickerLocator stickerLocator,
+                            @Nullable BlurHash blurHash)
   {
-    super(contentType, transferState, size, fileName, location, key, relay, digest, fastPreflightId, voiceNote, width, height, false, caption, stickerLocator);
+    super(contentType, transferState, size, fileName, location, key, relay, digest, fastPreflightId, voiceNote, width, height, false, caption, stickerLocator, blurHash);
   }
 
   @Nullable
@@ -99,7 +101,8 @@ public class PointerAttachment extends Attachment {
                                       pointer.get().asPointer().getWidth(),
                                       pointer.get().asPointer().getHeight(),
                                       pointer.get().asPointer().getCaption().orNull(),
-        stickerLocator));
+                                      stickerLocator,
+                                      BlurHash.parseOrNull(pointer.get().asPointer().getBlurHash().orNull())));
 
   }
 
@@ -119,6 +122,7 @@ public class PointerAttachment extends Attachment {
                                              thumbnail != null ? thumbnail.asPointer().getWidth() : 0,
                                              thumbnail != null ? thumbnail.asPointer().getHeight() : 0,
                                              thumbnail != null ? thumbnail.asPointer().getCaption().orNull() : null,
+                                             null,
                                              null));
   }
 }

src/org/thoughtcrime/securesms/attachments/TombstoneAttachment.java

@@ -16,7 +16,7 @@ import org.thoughtcrime.securesms.database.AttachmentDatabase;
 public class TombstoneAttachment extends Attachment {
 
   public TombstoneAttachment(@NonNull String contentType, boolean quote) {
-    super(contentType, AttachmentDatabase.TRANSFER_PROGRESS_DONE, 0, null, null, null, null, null, null, false, 0, 0, quote, null, null);
+    super(contentType, AttachmentDatabase.TRANSFER_PROGRESS_DONE, 0, null, null, null, null, null, null, false, 0, 0, quote, null, null, null);
   }
 
   @Override

src/org/thoughtcrime/securesms/attachments/UriAttachment.java

@@ -4,6 +4,7 @@ import android.net.Uri;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.stickers.StickerLocator;
 
 public class UriAttachment extends Attachment {
@@ -13,17 +14,18 @@ public class UriAttachment extends Attachment {
 
   public UriAttachment(@NonNull Uri uri, @NonNull String contentType, int transferState, long size,
                        @Nullable String fileName, boolean voiceNote, boolean quote, @Nullable String caption,
-                       @Nullable StickerLocator stickerLocator)
+                       @Nullable StickerLocator stickerLocator, @Nullable BlurHash blurHash)
   {
-    this(uri, uri, contentType, transferState, size, 0, 0, fileName, null, voiceNote, quote, caption, stickerLocator);
+    this(uri, uri, contentType, transferState, size, 0, 0, fileName, null, voiceNote, quote, caption, stickerLocator, blurHash);
   }
 
   public UriAttachment(@NonNull Uri dataUri, @Nullable Uri thumbnailUri,
                        @NonNull String contentType, int transferState, long size, int width, int height,
                        @Nullable String fileName, @Nullable String fastPreflightId,
-                       boolean voiceNote, boolean quote, @Nullable String caption, @Nullable StickerLocator stickerLocator)
+                       boolean voiceNote, boolean quote, @Nullable String caption, @Nullable StickerLocator stickerLocator,
+                       @Nullable BlurHash blurHash)
   {
-    super(contentType, transferState, size, fileName, null, null, null, null, fastPreflightId, voiceNote, width, height, quote, caption, stickerLocator);
+    super(contentType, transferState, size, fileName, null, null, null, null, fastPreflightId, voiceNote, width, height, quote, caption, stickerLocator, blurHash);
     this.dataUri      = dataUri;
     this.thumbnailUri = thumbnailUri;
   }

src/org/thoughtcrime/securesms/blurhash/Base83.java

@@ -0,0 +1,75 @@
+/**
+ * Source: https://github.com/hsch/blurhash-java
+ *
+ * Copyright (c) 2019 Hendrik Schnepel
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+ * associated documentation files (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge, publish, distribute,
+ * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+ * NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package org.thoughtcrime.securesms.blurhash;
+
+import android.text.TextUtils;
+
+import androidx.annotation.Nullable;
+
+final class Base83 {
+
+  private static final int MAX_LENGTH = 90;
+
+  private static final char[]ALPHABET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz#$%*+,-.:;=?@[]^_{|}~".toCharArray();
+
+  private static int indexOf(char[] a, char key) {
+    for (int i = 0; i < a.length; i++) {
+      if (a[i] == key) {
+        return i;
+      }
+    }
+    return -1;
+  }
+
+  static void encode(long value, int length, char[] buffer, int offset) {
+    int exp = 1;
+    for (int i = 1; i <= length; i++, exp *= 83) {
+      int digit = (int)(value / exp % 83);
+      buffer[offset + length - i] = ALPHABET[digit];
+    }
+  }
+
+  static int decode(String value, int fromInclusive, int toExclusive) {
+    int result = 0;
+    char[] chars = value.toCharArray();
+    for (int i = fromInclusive; i < toExclusive; i++) {
+      result = result * 83 + indexOf(ALPHABET, chars[i]);
+    }
+    return result;
+  }
+
+  static boolean isValid(@Nullable String value) {
+    if (value == null) return false;
+    final int length = value.length();
+
+    if (length == 0 || length > MAX_LENGTH) return false;
+
+    for (int i = 0; i < length; i++) {
+      if (indexOf(ALPHABET, value.charAt(i)) == -1) return false;
+    }
+
+    return true;
+  }
+
+  private Base83() {
+  }
+}
+

src/org/thoughtcrime/securesms/blurhash/BlurHash.java

@@ -0,0 +1,43 @@
+package org.thoughtcrime.securesms.blurhash;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import java.util.Objects;
+
+/**
+ * A BlurHash is a compact string representation of a blurred image that we can use to show fast
+ * image previews.
+ */
+public class BlurHash {
+
+  private final String hash;
+
+  private BlurHash(@NonNull String hash) {
+    this.hash = hash;
+  }
+
+  public static @Nullable BlurHash parseOrNull(@Nullable String hash) {
+    if (Base83.isValid(hash)) {
+      return new BlurHash(hash);
+    }
+    return null;
+  }
+
+  public @NonNull String getHash() {
+    return hash;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    BlurHash blurHash = (BlurHash) o;
+    return Objects.equals(hash, blurHash.hash);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(hash);
+  }
+}

src/org/thoughtcrime/securesms/blurhash/BlurHashDecoder.java

@@ -0,0 +1,113 @@
+/**
+ * Source: https://github.com/woltapp/blurhash
+ *
+ * Copyright (c) 2018 Wolt Enterprises
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+ * associated documentation files (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge, publish, distribute,
+ * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+ * NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package org.thoughtcrime.securesms.blurhash;
+
+import android.graphics.Bitmap;
+import android.graphics.Color;
+
+import androidx.annotation.Nullable;
+
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.linearTosRGB;
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.sRGBToLinear;
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.signPow;
+
+class BlurHashDecoder {
+
+  static @Nullable Bitmap decode(@Nullable String blurHash, int width, int height) {
+    return decode(blurHash, width, height, 1f);
+  }
+
+  static @Nullable Bitmap decode(@Nullable String blurHash, int width, int height, double punch) {
+
+    if (blurHash == null || blurHash.length() < 6) {
+      return null;
+    }
+
+    int numCompEnc = Base83.decode(blurHash, 0, 1);
+    int numCompX   = (numCompEnc % 9) + 1;
+    int numCompY   = (numCompEnc / 9) + 1;
+
+    if (blurHash.length() != 4 + 2 * numCompX * numCompY) {
+      return null;
+    }
+
+    int        maxAcEnc = Base83.decode(blurHash, 1, 2);
+    double     maxAc    = (maxAcEnc + 1) / 166f;
+    double[][] colors   = new double[numCompX * numCompY][];
+    for (int i = 0; i < colors.length; i++) {
+      if (i == 0) {
+        int colorEnc = Base83.decode(blurHash, 2, 6);
+        colors[i] = decodeDc(colorEnc);
+      } else {
+        int from = 4 + i * 2;
+        int colorEnc = Base83.decode(blurHash, from, from + 2);
+        colors[i] = decodeAc(colorEnc, maxAc * punch);
+      }
+    }
+
+    return composeBitmap(width, height, numCompX, numCompY, colors);
+  }
+
+  private static double[] decodeDc(int colorEnc) {
+    int r = colorEnc >> 16;
+    int g = (colorEnc >> 8) & 255;
+    int b = colorEnc & 255;
+    return new double[] {sRGBToLinear(r),
+                         sRGBToLinear(g),
+                         sRGBToLinear(b)};
+  }
+
+  private static double[] decodeAc(int value, double maxAc) {
+    int r = value / (19 * 19);
+    int g = (value / 19) % 19;
+    int b = value % 19;
+    return new double[]{
+        signPow((r - 9) / 9.0f, 2f) * maxAc,
+        signPow((g - 9) / 9.0f, 2f) * maxAc,
+        signPow((b - 9) / 9.0f, 2f) * maxAc
+    };
+  }
+
+  private static Bitmap composeBitmap(int width, int height, int numCompX, int numCompY, double[][] colors) {
+    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+    for (int y = 0; y < height; y++) {
+      for (int x = 0; x < width; x++) {
+
+        double r = 0f;
+        double g = 0f;
+        double b = 0f;
+
+        for (int j = 0; j < numCompY; j++) {
+          for (int i = 0; i < numCompX; i++) {
+            double basis = (Math.cos(Math.PI * x * i / width) * Math.cos(Math.PI * y * j / height));
+            double[] color = colors[j * numCompX + i];
+            r += color[0] * basis;
+            g += color[1] * basis;
+            b += color[2] * basis;
+          }
+        }
+        bitmap.setPixel(x, y, Color.rgb((int) linearTosRGB(r), (int) linearTosRGB(g), (int) linearTosRGB(b)));
+      }
+    }
+
+    return bitmap;
+  }
+}

src/org/thoughtcrime/securesms/blurhash/BlurHashEncoder.java

@@ -0,0 +1,148 @@
+/**
+ * Source: https://github.com/hsch/blurhash-java
+ *
+ * Copyright (c) 2019 Hendrik Schnepel
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+ * associated documentation files (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge, publish, distribute,
+ * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+ * NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+package org.thoughtcrime.securesms.blurhash;
+
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import java.io.InputStream;
+
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.linearTosRGB;
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.max;
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.sRGBToLinear;
+import static org.thoughtcrime.securesms.blurhash.BlurHashUtil.signPow;
+
+public final class BlurHashEncoder {
+
+  private BlurHashEncoder() {
+  }
+
+  public static @Nullable String encode(InputStream inputStream) {
+    BitmapFactory.Options options = new BitmapFactory.Options();
+    options.inSampleSize = 16;
+
+    Bitmap bitmap = BitmapFactory.decodeStream(inputStream, null, options);
+    if (bitmap == null) return null;
+
+    String hash = encode(bitmap);
+
+    bitmap.recycle();
+
+    return hash;
+  }
+
+  public static @Nullable String encode(@NonNull Bitmap bitmap) {
+    return encode(bitmap, 4, 3);
+  }
+
+  static String encode(Bitmap bitmap, int componentX, int componentY) {
+    int width    = bitmap.getWidth();
+    int height   = bitmap.getHeight();
+    int[] pixels = new int[width * height];
+    bitmap.getPixels(pixels, 0, width, 0, 0, width, height);
+    return encode(pixels, width, height, componentX, componentY);
+  }
+
+  private static String encode(int[] pixels, int width, int height, int componentX, int componentY) {
+
+    if (componentX < 1 || componentX > 9 || componentY < 1 || componentY > 9) {
+      throw new IllegalArgumentException("Blur hash must have between 1 and 9 components");
+    }
+    if (width * height != pixels.length) {
+      throw new IllegalArgumentException("Width and height must match the pixels array");
+    }
+
+    double[][] factors = new double[componentX * componentY][3];
+    for (int j = 0; j < componentY; j++) {
+      for (int i = 0; i < componentX; i++) {
+        double normalisation = i == 0 && j == 0 ? 1 : 2;
+        applyBasisFunction(pixels, width, height,
+            normalisation, i, j,
+            factors, j * componentX + i);
+      }
+    }
+
+    char[] hash = new char[1 + 1 + 4 + 2 * (factors.length - 1)]; // size flag + max AC + DC + 2 * AC components
+
+    long sizeFlag = componentX - 1 + (componentY - 1) * 9;
+    Base83.encode(sizeFlag, 1, hash, 0);
+
+    double maximumValue;
+    if (factors.length > 1) {
+      double actualMaximumValue    = max(factors, 1, factors.length);
+      double quantisedMaximumValue = Math.floor(Math.max(0, Math.min(82, Math.floor(actualMaximumValue * 166 - 0.5))));
+      maximumValue = (quantisedMaximumValue + 1) / 166;
+      Base83.encode(Math.round(quantisedMaximumValue), 1, hash, 1);
+    } else {
+      maximumValue = 1;
+      Base83.encode(0, 1, hash, 1);
+    }
+
+    double[] dc = factors[0];
+    Base83.encode(encodeDC(dc), 4, hash, 2);
+
+    for (int i = 1; i < factors.length; i++) {
+      Base83.encode(encodeAC(factors[i], maximumValue), 2, hash, 6 + 2 * (i - 1));
+    }
+    return new String(hash);
+  }
+
+  private static void applyBasisFunction(int[] pixels, int width, int height,
+                                         double normalisation, int i, int j,
+                                         double[][] factors, int index)
+  {
+    double r = 0, g = 0, b = 0;
+    for (int x = 0; x < width; x++) {
+      for (int y = 0; y < height; y++) {
+        double basis = normalisation
+                     * Math.cos((Math.PI * i * x) / width)
+                     * Math.cos((Math.PI * j * y) / height);
+        int pixel = pixels[y * width + x];
+        r += basis * sRGBToLinear((pixel >> 16) & 0xff);
+        g += basis * sRGBToLinear((pixel >> 8)  & 0xff);
+        b += basis * sRGBToLinear( pixel        & 0xff);
+      }
+    }
+    double scale = 1.0 / (width * height);
+    factors[index][0] = r * scale;
+    factors[index][1] = g * scale;
+    factors[index][2] = b * scale;
+  }
+
+  private static long encodeDC(double[] value) {
+    long r = linearTosRGB(value[0]);
+    long g = linearTosRGB(value[1]);
+    long b = linearTosRGB(value[2]);
+    return (r << 16) + (g << 8) + b;
+  }
+
+  private static long encodeAC(double[] value, double maximumValue) {
+    double quantR = Math.floor(Math.max(0, Math.min(18, Math.floor(signPow(value[0] / maximumValue, 0.5) * 9 + 9.5))));
+    double quantG = Math.floor(Math.max(0, Math.min(18, Math.floor(signPow(value[1] / maximumValue, 0.5) * 9 + 9.5))));
+    double quantB = Math.floor(Math.max(0, Math.min(18, Math.floor(signPow(value[2] / maximumValue, 0.5) * 9 + 9.5))));
+    return Math.round(quantR * 19 * 19 + quantG * 19 + quantB);
+  }
+
+}

src/org/thoughtcrime/securesms/blurhash/BlurHashModelLoader.java

@@ -0,0 +1,74 @@
+package org.thoughtcrime.securesms.blurhash;
+
+import androidx.annotation.NonNull;
+
+import com.bumptech.glide.Priority;
+import com.bumptech.glide.load.DataSource;
+import com.bumptech.glide.load.Options;
+import com.bumptech.glide.load.data.DataFetcher;
+import com.bumptech.glide.load.model.ModelLoader;
+import com.bumptech.glide.load.model.ModelLoaderFactory;
+import com.bumptech.glide.load.model.MultiModelLoaderFactory;
+import com.bumptech.glide.signature.ObjectKey;
+
+public final class BlurHashModelLoader implements ModelLoader<BlurHash, BlurHash> {
+
+  private BlurHashModelLoader() {}
+
+  @Override
+  public LoadData<BlurHash> buildLoadData(@NonNull BlurHash blurHash,
+                                          int width,
+                                          int height,
+                                          @NonNull Options options)
+  {
+    return new LoadData<>(new ObjectKey(blurHash.getHash()), new BlurDataFetcher(blurHash));
+  }
+
+  @Override
+  public boolean handles(@NonNull BlurHash blurHash) {
+    return true;
+  }
+
+  private final class BlurDataFetcher implements DataFetcher<BlurHash> {
+
+    private final BlurHash blurHash;
+
+    private BlurDataFetcher(@NonNull BlurHash blurHash) {
+      this.blurHash = blurHash;
+    }
+
+    @Override
+    public void loadData(@NonNull Priority priority, @NonNull DataCallback<? super BlurHash> callback) {
+      callback.onDataReady(blurHash);
+    }
+
+    @Override
+    public void cleanup() {
+    }
+
+    @Override
+    public void cancel() {
+    }
+
+    @Override
+    public @NonNull Class<BlurHash> getDataClass() {
+      return BlurHash.class;
+    }
+
+    @Override
+    public @NonNull DataSource getDataSource() {
+      return DataSource.LOCAL;
+    }
+  }
+
+  public static class Factory implements ModelLoaderFactory<BlurHash, BlurHash> {
+    @Override
+    public @NonNull ModelLoader<BlurHash, BlurHash> build(@NonNull MultiModelLoaderFactory multiFactory) {
+      return new BlurHashModelLoader();
+    }
+
+    @Override
+    public void teardown() {
+    }
+  }
+}

src/org/thoughtcrime/securesms/blurhash/BlurHashResourceDecoder.java

@@ -0,0 +1,39 @@
+package org.thoughtcrime.securesms.blurhash;
+
+import android.graphics.Bitmap;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.bumptech.glide.load.Options;
+import com.bumptech.glide.load.ResourceDecoder;
+import com.bumptech.glide.load.engine.Resource;
+import com.bumptech.glide.load.resource.SimpleResource;
+
+import java.io.IOException;
+
+public class BlurHashResourceDecoder implements ResourceDecoder<BlurHash, Bitmap> {
+
+  private static final int MAX_DIMEN = 20;
+
+  @Override
+  public boolean handles(@NonNull BlurHash source, @NonNull Options options) throws IOException {
+    return true;
+  }
+
+  @Override
+  public @Nullable Resource<Bitmap> decode(@NonNull BlurHash source, int width, int height, @NonNull Options options) throws IOException {
+    final int finalWidth;
+    final int finalHeight;
+
+    if (width > height) {
+      finalWidth  = Math.min(width, MAX_DIMEN);
+      finalHeight = (int) (finalWidth * height / (float) width);
+    } else {
+      finalHeight = Math.min(height, MAX_DIMEN);
+      finalWidth  = (int) (finalHeight * width / (float) height);
+    }
+
+    return new SimpleResource<>(BlurHashDecoder.decode(source.getHash(), finalWidth, finalHeight));
+  }
+}

src/org/thoughtcrime/securesms/blurhash/BlurHashUtil.java

@@ -0,0 +1,62 @@
+/**
+ * Source: https://github.com/hsch/blurhash-java
+ *
+ * Copyright (c) 2019 Hendrik Schnepel
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+ * associated documentation files (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge, publish, distribute,
+ * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+ * NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package org.thoughtcrime.securesms.blurhash;
+
+final class BlurHashUtil {
+
+  static double sRGBToLinear(long value) {
+    double v = value / 255.0;
+    if (v <= 0.04045) {
+      return v / 12.92;
+    } else {
+      return Math.pow((v + 0.055) / 1.055, 2.4);
+    }
+  }
+
+  static long linearTosRGB(double value) {
+    double v = Math.max(0, Math.min(1, value));
+    if (v <= 0.0031308) {
+      return (long)(v * 12.92 * 255 + 0.5);
+    } else {
+      return (long)((1.055 * Math.pow(v, 1 / 2.4) - 0.055) * 255 + 0.5);
+    }
+  }
+
+  static double signPow(double val, double exp) {
+    return Math.copySign(Math.pow(Math.abs(val), exp), val);
+  }
+
+  static double max(double[][] values, int from, int endExclusive) {
+    double result = Double.NEGATIVE_INFINITY;
+    for (int i = from; i < endExclusive; i++) {
+      for (int j = 0; j < values[i].length; j++) {
+        double value = values[i][j];
+        if (value > result) {
+          result = value;
+        }
+      }
+    }
+    return result;
+  }
+
+  private BlurHashUtil() {
+  }
+}

src/org/thoughtcrime/securesms/components/ThumbnailView.java

@@ -2,10 +2,13 @@ package org.thoughtcrime.securesms.components;
 
 import android.content.Context;
 import android.content.res.TypedArray;
+import android.graphics.Bitmap;
 import android.net.Uri;
 import androidx.annotation.NonNull;
 import androidx.annotation.UiThread;
 import android.util.AttributeSet;
+
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.logging.Log;
 import android.view.View;
 import android.view.ViewGroup;
@@ -36,6 +39,7 @@ import org.whispersystems.libsignal.util.guava.Optional;
 
 import java.util.Collections;
 import java.util.Locale;
+import java.util.Objects;
 
 import static com.bumptech.glide.load.resource.drawable.DrawableTransitionOptions.withCrossFade;
 
@@ -50,6 +54,7 @@ public class ThumbnailView extends FrameLayout {
   private static final int    MAX_HEIGHT = 3;
 
   private ImageView       image;
+  private ImageView       blurhash;
   private View            playOverlay;
   private View            captionIcon;
   private OnClickListener parentClickListener;
@@ -79,6 +84,7 @@ public class ThumbnailView extends FrameLayout {
     inflate(context, R.layout.thumbnail_view, this);
 
     this.image       = findViewById(R.id.thumbnail_image);
+    this.blurhash    = findViewById(R.id.thumbnail_blurhash);
     this.playOverlay = findViewById(R.id.play_overlay);
     this.captionIcon = findViewById(R.id.thumbnail_caption_icon);
     super.setOnClickListener(new ThumbnailClickDispatcher());
@@ -270,22 +276,37 @@ public class ThumbnailView extends FrameLayout {
                + ", progress " + slide.getTransferState() + ", fast preflight id: " +
                slide.asAttachment().getFastPreflightId());
 
+    BlurHash previousBlurhash = this.slide != null ? this.slide.getPlaceholderBlur() : null;
+
     this.slide = slide;
 
     this.captionIcon.setVisibility(slide.getCaption().isPresent() ? VISIBLE : GONE);
 
     dimens[WIDTH]  = naturalWidth;
     dimens[HEIGHT] = naturalHeight;
+
     invalidate();
 
-    SettableFuture<Boolean> result = new SettableFuture<>();
+    SettableFuture<Boolean> result        = new SettableFuture<>();
+    boolean                 resultHandled = false;
+
+    if (slide.hasPlaceholder() && !Objects.equals(slide.getPlaceholderBlur(), previousBlurhash)) {
+      buildPlaceholderGlideRequest(glideRequests, slide).into(new GlideBitmapListeningTarget(blurhash, result));
+      resultHandled = true;
+    } else if (!slide.hasPlaceholder()) {
+      glideRequests.clear(blurhash);
+      blurhash.setImageDrawable(null);
+    }
 
     if (slide.getThumbnailUri() != null) {
       buildThumbnailGlideRequest(glideRequests, slide).into(new GlideDrawableListeningTarget(image, result));
-    } else if (slide.hasPlaceholder()) {
-      buildPlaceholderGlideRequest(glideRequests, slide).into(new GlideBitmapListeningTarget(image, result));
+      resultHandled = true;
     } else {
       glideRequests.clear(image);
+      image.setImageDrawable(null);
+    }
+
+    if (!resultHandled) {
       result.set(false);
     }
 
@@ -308,6 +329,7 @@ public class ThumbnailView extends FrameLayout {
     }
 
     request.into(new GlideDrawableListeningTarget(image, future));
+    blurhash.setImageDrawable(null);
 
     return future;
   }
@@ -352,9 +374,16 @@ public class ThumbnailView extends FrameLayout {
   }
 
   private RequestBuilder buildPlaceholderGlideRequest(@NonNull GlideRequests glideRequests, @NonNull Slide slide) {
-    return applySizing(glideRequests.asBitmap()
-                        .load(slide.getPlaceholderRes(getContext().getTheme()))
-                        .diskCacheStrategy(DiskCacheStrategy.NONE), new FitCenter());
+    GlideRequest<Bitmap> bitmap          = glideRequests.asBitmap();
+    BlurHash             placeholderBlur = slide.getPlaceholderBlur();
+
+    if (placeholderBlur != null) {
+      bitmap = bitmap.load(placeholderBlur);
+    } else {
+      bitmap = bitmap.load(slide.getPlaceholderRes(getContext().getTheme()));
+    }
+
+    return applySizing(bitmap.diskCacheStrategy(DiskCacheStrategy.NONE), new CenterCrop());
   }
 
   private GlideRequest applySizing(@NonNull GlideRequest request, @NonNull BitmapTransformation fitting) {

src/org/thoughtcrime/securesms/contactshare/Contact.java

@@ -14,6 +14,7 @@ import com.fasterxml.jackson.annotation.JsonProperty;
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.AttachmentId;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.util.JsonUtils;
 import org.thoughtcrime.securesms.util.MediaUtil;
@@ -642,7 +643,7 @@ public class Contact implements Parcelable {
 
     private static Attachment attachmentFromUri(@Nullable Uri uri) {
       if (uri == null) return null;
-      return new UriAttachment(uri, MediaUtil.IMAGE_JPEG, AttachmentDatabase.TRANSFER_PROGRESS_DONE, 0, null, false, false, null, null);
+      return new UriAttachment(uri, MediaUtil.IMAGE_JPEG, AttachmentDatabase.TRANSFER_PROGRESS_DONE, 0, null, false, false, null, null, null);
     }
 
     @Override

src/org/thoughtcrime/securesms/conversation/ConversationActivity.java

@@ -100,6 +100,7 @@ import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.TombstoneAttachment;
 import org.thoughtcrime.securesms.audio.AudioRecorder;
 import org.thoughtcrime.securesms.audio.AudioSlidePlayer;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.color.MaterialColor;
 import org.thoughtcrime.securesms.components.AnimatingToggle;
 import org.thoughtcrime.securesms.components.AttachmentTypeSelector;
@@ -586,7 +587,7 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
         } else if (MediaUtil.isGif(mediaItem.getMimeType())) {
           slideDeck.addSlide(new GifSlide(this, mediaItem.getUri(), 0, mediaItem.getWidth(), mediaItem.getHeight(), mediaItem.getCaption().orNull()));
         } else if (MediaUtil.isImageType(mediaItem.getMimeType())) {
-          slideDeck.addSlide(new ImageSlide(this, mediaItem.getUri(), 0, mediaItem.getWidth(), mediaItem.getHeight(), mediaItem.getCaption().orNull()));
+          slideDeck.addSlide(new ImageSlide(this, mediaItem.getUri(), 0, mediaItem.getWidth(), mediaItem.getHeight(), mediaItem.getCaption().orNull(), null));
         } else {
           Log.w(TAG, "Asked to send an unexpected mimeType: '" + mediaItem.getMimeType() + "'. Skipping.");
         }

src/org/thoughtcrime/securesms/database/AttachmentDatabase.java

@@ -42,6 +42,7 @@ import org.json.JSONException;
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.AttachmentId;
 import org.thoughtcrime.securesms.attachments.DatabaseAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.crypto.AttachmentSecret;
 import org.thoughtcrime.securesms.crypto.ClassicDecryptingPartInputStream;
 import org.thoughtcrime.securesms.crypto.ModernDecryptingPartInputStream;
@@ -112,6 +113,7 @@ public class AttachmentDatabase extends Database {
           static final String HEIGHT                 = "height";
           static final String CAPTION                = "caption";
           static final String DATA_HASH              = "data_hash";
+          static final String BLUR_HASH              = "blur_hash";
 
   public  static final String DIRECTORY              = "parts";
 
@@ -130,7 +132,7 @@ public class AttachmentDatabase extends Database {
                                                            UNIQUE_ID, DIGEST, FAST_PREFLIGHT_ID, VOICE_NOTE,
                                                            QUOTE, DATA_RANDOM, THUMBNAIL_RANDOM, WIDTH, HEIGHT,
                                                            CAPTION, STICKER_PACK_ID, STICKER_PACK_KEY, STICKER_ID,
-                                                           DATA_HASH};
+                                                           DATA_HASH, BLUR_HASH};
 
   public static final String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME + " (" + ROW_ID + " INTEGER PRIMARY KEY, " +
     MMS_ID + " INTEGER, " + "seq" + " INTEGER DEFAULT 0, "                        +
@@ -145,7 +147,7 @@ public class AttachmentDatabase extends Database {
     QUOTE + " INTEGER DEFAULT 0, " + WIDTH + " INTEGER DEFAULT 0, " + HEIGHT + " INTEGER DEFAULT 0, " +
     CAPTION + " TEXT DEFAULT NULL, " + STICKER_PACK_ID + " TEXT DEFAULT NULL, " +
     STICKER_PACK_KEY + " DEFAULT NULL, " + STICKER_ID + " INTEGER DEFAULT -1, " +
-    DATA_HASH + " TEXT DEFAULT NULL);";
+    DATA_HASH + " TEXT DEFAULT NULL, " + BLUR_HASH + " TEXT DEFAULT NULL);";
 
   public static final String[] CREATE_INDEXS = {
     "CREATE INDEX IF NOT EXISTS part_mms_id_index ON " + TABLE_NAME + " (" + MMS_ID + ");",
@@ -342,6 +344,7 @@ public class AttachmentDatabase extends Database {
     values.put(WIDTH, 0);
     values.put(HEIGHT, 0);
     values.put(TRANSFER_STATE, TRANSFER_PROGRESS_DONE);
+    values.put(BLUR_HASH, (String) null);
 
     database.update(TABLE_NAME, values, MMS_ID + " = ?", new String[] {mmsId + ""});
     notifyAttachmentListeners();
@@ -456,6 +459,10 @@ public class AttachmentDatabase extends Database {
       values.put(DATA_HASH, dataInfo.hash);
     }
 
+    if (placeholder != null && placeholder.getBlurHash() != null) {
+      values.put(BLUR_HASH, placeholder.getBlurHash().getHash());
+    }
+
     values.put(TRANSFER_STATE, TRANSFER_PROGRESS_DONE);
     values.put(CONTENT_LOCATION, (String)null);
     values.put(CONTENT_DISPOSITION, (String)null);
@@ -474,6 +481,11 @@ public class AttachmentDatabase extends Database {
     thumbnailExecutor.submit(new ThumbnailFetchCallable(attachmentId));
   }
 
+  private static @Nullable String getBlurHashStringOrNull(@Nullable BlurHash blurHash) {
+    if (blurHash == null) return null;
+    return blurHash.getHash();
+  }
+
   public void copyAttachmentData(@NonNull AttachmentId sourceId, @NonNull AttachmentId destinationId)
       throws MmsException
   {
@@ -507,7 +519,7 @@ public class AttachmentDatabase extends Database {
     contentValues.put(WIDTH, sourceAttachment.getWidth());
     contentValues.put(HEIGHT, sourceAttachment.getHeight());
     contentValues.put(CONTENT_TYPE, sourceAttachment.getContentType());
-
+    contentValues.put(BLUR_HASH, getBlurHashStringOrNull(sourceAttachment.getBlurHash()));
 
     database.update(TABLE_NAME, contentValues, PART_ID_WHERE, destinationId.toStrings());
   }
@@ -523,6 +535,7 @@ public class AttachmentDatabase extends Database {
     values.put(NAME, attachment.getRelay());
     values.put(SIZE, attachment.getSize());
     values.put(FAST_PREFLIGHT_ID, attachment.getFastPreflightId());
+    values.put(BLUR_HASH, getBlurHashStringOrNull(attachment.getBlurHash()));
 
     database.update(TABLE_NAME, values, PART_ID_WHERE, id.toStrings());
   }
@@ -862,7 +875,8 @@ public class AttachmentDatabase extends Database {
                                                   ? new StickerLocator(object.getString(STICKER_PACK_ID),
                                                                        object.getString(STICKER_PACK_KEY),
                                                                        object.getInt(STICKER_ID))
-                                                  : null));
+                                                  : null,
+                                              BlurHash.parseOrNull(object.getString(BLUR_HASH))));
           }
         }
 
@@ -891,7 +905,8 @@ public class AttachmentDatabase extends Database {
                                                                     ? new StickerLocator(cursor.getString(cursor.getColumnIndexOrThrow(STICKER_PACK_ID)),
                                                                                          cursor.getString(cursor.getColumnIndexOrThrow(STICKER_PACK_KEY)),
                                                                                          cursor.getInt(cursor.getColumnIndexOrThrow(STICKER_ID)))
-                                                                    : null));
+                                                                    : null,
+                                                                BlurHash.parseOrNull(cursor.getString(cursor.getColumnIndex(BLUR_HASH)))));
       }
     } catch (JSONException e) {
       throw new AssertionError(e);
@@ -930,6 +945,7 @@ public class AttachmentDatabase extends Database {
     contentValues.put(HEIGHT, attachment.getHeight());
     contentValues.put(QUOTE, quote);
     contentValues.put(CAPTION, attachment.getCaption());
+    contentValues.put(BLUR_HASH, getBlurHashStringOrNull(attachment.getBlurHash()));
 
     if (attachment.isSticker()) {
       contentValues.put(STICKER_PACK_ID, attachment.getSticker().getPackId());

src/org/thoughtcrime/securesms/database/MediaDatabase.java

@@ -37,6 +37,7 @@ public class MediaDatabase extends Database {
         + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_PACK_ID + ", "
         + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_PACK_KEY + ", "
         + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_ID + ", "
+        + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.BLUR_HASH + ", "
         + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.CAPTION + ", "
         + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.NAME + ", "
         + MmsDatabase.TABLE_NAME + "." + MmsDatabase.MESSAGE_BOX + ", "

src/org/thoughtcrime/securesms/database/MmsDatabase.java

@@ -174,7 +174,8 @@ public class MmsDatabase extends MessagingDatabase {
           "'" + AttachmentDatabase.CAPTION + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.CAPTION + ", " +
           "'" + AttachmentDatabase.STICKER_PACK_ID + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_PACK_ID+ ", " +
           "'" + AttachmentDatabase.STICKER_PACK_KEY + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_PACK_KEY + ", " +
-          "'" + AttachmentDatabase.STICKER_ID + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_ID +
+          "'" + AttachmentDatabase.STICKER_ID + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_ID + ", " +
+          "'" + AttachmentDatabase.BLUR_HASH + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.BLUR_HASH +
           ")) AS " + AttachmentDatabase.ATTACHMENT_JSON_ALIAS,
   };
 
@@ -795,7 +796,8 @@ public class MmsDatabase extends MessagingDatabase {
                                                databaseAttachment.getHeight(),
                                                databaseAttachment.isQuote(),
                                                databaseAttachment.getCaption(),
-                                               databaseAttachment.getSticker()));
+                                               databaseAttachment.getSticker(),
+                                               databaseAttachment.getBlurHash()));
       }
 
       return insertMediaMessage(request.getBody(),

src/org/thoughtcrime/securesms/database/MmsSmsDatabase.java

@@ -255,7 +255,8 @@ public class MmsSmsDatabase extends Database {
                                   "'" + AttachmentDatabase.CAPTION + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.CAPTION + ", " +
                                   "'" + AttachmentDatabase.STICKER_PACK_ID + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_PACK_ID + ", " +
                                   "'" + AttachmentDatabase.STICKER_PACK_KEY + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_PACK_KEY + ", " +
-                                  "'" + AttachmentDatabase.STICKER_ID + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_ID +
+                                  "'" + AttachmentDatabase.STICKER_ID + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.STICKER_ID + ", " +
+                                  "'" + AttachmentDatabase.BLUR_HASH + "', " + AttachmentDatabase.TABLE_NAME + "." + AttachmentDatabase.BLUR_HASH +
                                   ")) AS " + AttachmentDatabase.ATTACHMENT_JSON_ALIAS,
                               SmsDatabase.BODY, MmsSmsColumns.READ, MmsSmsColumns.THREAD_ID,
                               SmsDatabase.TYPE, SmsDatabase.RECIPIENT_ID, SmsDatabase.ADDRESS_DEVICE_ID, SmsDatabase.SUBJECT, MmsDatabase.MESSAGE_TYPE,

src/org/thoughtcrime/securesms/database/helpers/SQLCipherOpenHelper.java

@@ -84,8 +84,9 @@ public class SQLCipherOpenHelper extends SQLiteOpenHelper {
   private static final int MMS_RECIPIENT_CLEANUP            = 27;
   private static final int ATTACHMENT_HASHING               = 28;
   private static final int NOTIFICATION_RECIPIENT_IDS       = 29;
+  private static final int BLUR_HASH                        = 30;
 
-  private static final int    DATABASE_VERSION = 29;
+  private static final int    DATABASE_VERSION = 30;
   private static final String DATABASE_NAME    = "signal.db";
 
   private final Context        context;
@@ -584,6 +585,10 @@ public class SQLCipherOpenHelper extends SQLiteOpenHelper {
         }
       }
 
+      if (oldVersion < BLUR_HASH) {
+        db.execSQL("ALTER TABLE part ADD COLUMN blur_hash TEXT DEFAULT NULL");
+      }
+
       db.setTransactionSuccessful();
     } finally {
       db.endTransaction();

src/org/thoughtcrime/securesms/groups/V1GroupManager.java

@@ -10,6 +10,7 @@ import com.google.protobuf.ByteString;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.database.GroupDatabase;
@@ -111,7 +112,7 @@ final class V1GroupManager {
 
       if (avatar != null) {
         Uri avatarUri = BlobProvider.getInstance().forData(avatar).createForSingleUseInMemory();
-        avatarAttachment = new UriAttachment(avatarUri, MediaUtil.IMAGE_PNG, AttachmentDatabase.TRANSFER_PROGRESS_DONE, avatar.length, null, false, false, null, null);
+        avatarAttachment = new UriAttachment(avatarUri, MediaUtil.IMAGE_PNG, AttachmentDatabase.TRANSFER_PROGRESS_DONE, avatar.length, null, false, false, null, null, null);
       }
 
       OutgoingGroupMediaMessage outgoingMessage = new OutgoingGroupMediaMessage(groupRecipient, groupContext, avatarAttachment, System.currentTimeMillis(), 0, false, null, Collections.emptyList(), Collections.emptyList());

src/org/thoughtcrime/securesms/jobs/AttachmentDownloadJob.java

@@ -8,6 +8,7 @@ import org.greenrobot.eventbus.EventBus;
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.AttachmentId;
 import org.thoughtcrime.securesms.attachments.DatabaseAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
@@ -210,7 +211,8 @@ public class AttachmentDownloadJob extends BaseJob {
                                                 Optional.fromNullable(attachment.getDigest()),
                                                 Optional.fromNullable(attachment.getFileName()),
                                                 attachment.isVoiceNote(),
-                                                Optional.absent());
+                                                Optional.absent(),
+                                                Optional.fromNullable(attachment.getBlurHash()).transform(BlurHash::getHash));
     } catch (IOException | ArithmeticException e) {
       Log.w(TAG, e);
       throw new InvalidPartException(e);

src/org/thoughtcrime/securesms/jobs/AttachmentUploadJob.java

@@ -1,5 +1,10 @@
 package org.thoughtcrime.securesms.jobs;
 
+import android.graphics.Bitmap;
+import android.media.MediaDataSource;
+import android.media.MediaMetadataRetriever;
+import android.os.Build;
+
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
@@ -9,6 +14,7 @@ import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.AttachmentId;
 import org.thoughtcrime.securesms.attachments.DatabaseAttachment;
 import org.thoughtcrime.securesms.attachments.PointerAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHashEncoder;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
@@ -20,6 +26,7 @@ import org.thoughtcrime.securesms.logging.Log;
 import org.thoughtcrime.securesms.mms.PartAuthority;
 import org.thoughtcrime.securesms.service.GenericForegroundService;
 import org.thoughtcrime.securesms.service.NotificationController;
+import org.thoughtcrime.securesms.util.MediaUtil;
 import org.whispersystems.libsignal.util.guava.Optional;
 import org.whispersystems.signalservice.api.SignalServiceMessageSender;
 import org.whispersystems.signalservice.api.messages.SignalServiceAttachment;
@@ -116,27 +123,76 @@ public final class AttachmentUploadJob extends BaseJob {
     try {
       if (attachment.getDataUri() == null || attachment.getSize() == 0) throw new IOException("Assertion failed, outgoing attachment has no data!");
       InputStream is = PartAuthority.getAttachmentStream(context, attachment.getDataUri());
-      return SignalServiceAttachment.newStreamBuilder()
-                                    .withStream(is)
-                                    .withContentType(attachment.getContentType())
-                                    .withLength(attachment.getSize())
-                                    .withFileName(attachment.getFileName())
-                                    .withVoiceNote(attachment.isVoiceNote())
-                                    .withWidth(attachment.getWidth())
-                                    .withHeight(attachment.getHeight())
-                                    .withCaption(attachment.getCaption())
-                                    .withListener((total, progress) -> {
-                                      EventBus.getDefault().postSticky(new PartProgressEvent(attachment, PartProgressEvent.Type.NETWORK, total, progress));
-                                      if (notification != null) {
-                                        notification.setProgress(total, progress);
-                                      }
-                                    })
-                                    .build();
+      SignalServiceAttachment.Builder builder = SignalServiceAttachment.newStreamBuilder()
+                                                                       .withStream(is)
+                                                                       .withContentType(attachment.getContentType())
+                                                                       .withLength(attachment.getSize())
+                                                                       .withFileName(attachment.getFileName())
+                                                                       .withVoiceNote(attachment.isVoiceNote())
+                                                                       .withWidth(attachment.getWidth())
+                                                                       .withHeight(attachment.getHeight())
+                                                                       .withCaption(attachment.getCaption())
+                                                                       .withListener((total, progress) -> {
+                                                                         EventBus.getDefault().postSticky(new PartProgressEvent(attachment, PartProgressEvent.Type.NETWORK, total, progress));
+                                                                         if (notification != null) {
+                                                                           notification.setProgress(total, progress);
+                                                                         }
+                                                                       });
+      if (MediaUtil.isImageType(attachment.getContentType())) {
+        return builder.withBlurHash(getImageBlurHash(attachment)).build();
+      } else if (MediaUtil.isVideoType(attachment.getContentType())) {
+        return builder.withBlurHash(getVideoBlurHash(attachment)).build();
+      } else {
+        return builder.build();
+      }
+
     } catch (IOException ioe) {
       throw new InvalidAttachmentException(ioe);
     }
   }
 
+  private @Nullable String getImageBlurHash(@NonNull Attachment attachment) throws IOException {
+    if (attachment.getBlurHash() != null) return attachment.getBlurHash().getHash();
+    if (attachment.getDataUri() == null) return null;
+
+    return BlurHashEncoder.encode(PartAuthority.getAttachmentStream(context, attachment.getDataUri()));
+  }
+
+  private @Nullable String getVideoBlurHash(@NonNull Attachment attachment) throws IOException {
+    if (attachment.getThumbnailUri() != null) {
+      return BlurHashEncoder.encode(PartAuthority.getAttachmentStream(context, attachment.getThumbnailUri()));
+    }
+
+    if (attachment.getBlurHash() != null) return attachment.getBlurHash().getHash();
+
+    if (Build.VERSION.SDK_INT < 23) {
+      Log.w(TAG, "Video thumbnails not supported...");
+      return null;
+    }
+
+    try (MediaDataSource dataSource = DatabaseFactory.getAttachmentDatabase(context).mediaDataSourceFor(attachmentId)) {
+      if (dataSource == null) return null;
+
+      MediaMetadataRetriever retriever = new MediaMetadataRetriever();
+      retriever.setDataSource(dataSource);
+
+      Bitmap bitmap = retriever.getFrameAtTime(1000);
+
+      if (bitmap != null) {
+        Bitmap thumb = Bitmap.createScaledBitmap(bitmap, 100, 100, false);
+        bitmap.recycle();
+
+        Log.i(TAG, "Generated video thumbnail...");
+        String hash = BlurHashEncoder.encode(thumb);
+        thumb.recycle();
+
+        return hash;
+      } else {
+        return null;
+      }
+    }
+  }
+
   private class InvalidAttachmentException extends Exception {
     InvalidAttachmentException(String message) {
       super(message);

src/org/thoughtcrime/securesms/jobs/AvatarDownloadJob.java

@@ -89,7 +89,7 @@ public class AvatarDownloadJob extends BaseJob {
         attachment.deleteOnExit();
 
         SignalServiceMessageReceiver   receiver    = ApplicationDependencies.getSignalServiceMessageReceiver();
-        SignalServiceAttachmentPointer pointer     = new SignalServiceAttachmentPointer(avatarId, contentType, key, Optional.of(0), Optional.absent(), 0, 0, digest, fileName, false, Optional.absent());
+        SignalServiceAttachmentPointer pointer     = new SignalServiceAttachmentPointer(avatarId, contentType, key, Optional.of(0), Optional.absent(), 0, 0, digest, fileName, false, Optional.absent(), Optional.absent());
         InputStream                    inputStream = receiver.retrieveAttachment(pointer, attachment, MAX_AVATAR_SIZE);
         Bitmap                         avatar      = BitmapUtil.createScaledBitmap(context, new AttachmentModel(attachment, key, 0, digest), 500, 500);
 

src/org/thoughtcrime/securesms/jobs/MmsDownloadJob.java

@@ -13,6 +13,7 @@ import com.google.android.mms.pdu_alt.RetrieveConf;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.Address;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
@@ -229,7 +230,7 @@ public class MmsDownloadJob extends BaseJob {
 
           attachments.add(new UriAttachment(uri, Util.toIsoString(part.getContentType()),
                                             AttachmentDatabase.TRANSFER_PROGRESS_DONE,
-                                            part.getData().length, name, false, false, null, null));
+                                            part.getData().length, name, false, false, null, null, null));
         }
       }
     }

src/org/thoughtcrime/securesms/jobs/PushDecryptJob.java

@@ -35,6 +35,7 @@ import org.thoughtcrime.securesms.attachments.DatabaseAttachment;
 import org.thoughtcrime.securesms.attachments.PointerAttachment;
 import org.thoughtcrime.securesms.attachments.TombstoneAttachment;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.contactshare.Contact;
 import org.thoughtcrime.securesms.contactshare.ContactModelMapper;
 import org.thoughtcrime.securesms.crypto.IdentityKeyUtil;
@@ -1250,7 +1251,8 @@ public class PushDecryptJob extends BaseJob {
                                            false,
                                            false,
                                            null,
-                                           stickerLocator));
+                                           stickerLocator,
+                                           null));
     } else {
       return Optional.of(PointerAttachment.forPointer(Optional.of(sticker.get().getAttachment()), stickerLocator).get());
     }

src/org/thoughtcrime/securesms/jobs/PushSendJob.java

@@ -11,17 +11,15 @@ import com.annimon.stream.Stream;
 import org.greenrobot.eventbus.EventBus;
 import org.signal.libsignal.metadata.certificate.InvalidCertificateException;
 import org.signal.libsignal.metadata.certificate.SenderCertificate;
-import org.thoughtcrime.securesms.ApplicationContext;
 import org.thoughtcrime.securesms.TextSecureExpiredException;
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.DatabaseAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.contactshare.Contact;
 import org.thoughtcrime.securesms.contactshare.ContactModelMapper;
 import org.thoughtcrime.securesms.crypto.ProfileKeyUtil;
 import org.thoughtcrime.securesms.database.Address;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
-import org.thoughtcrime.securesms.database.MmsDatabase;
-import org.thoughtcrime.securesms.database.NoSuchMessageException;
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
 import org.thoughtcrime.securesms.events.PartProgressEvent;
 import org.thoughtcrime.securesms.jobmanager.Job;
@@ -30,7 +28,6 @@ import org.thoughtcrime.securesms.jobmanager.impl.NetworkConstraint;
 import org.thoughtcrime.securesms.linkpreview.LinkPreview;
 import org.thoughtcrime.securesms.logging.Log;
 import org.thoughtcrime.securesms.mms.DecryptableStreamUriLoader;
-import org.thoughtcrime.securesms.mms.MmsException;
 import org.thoughtcrime.securesms.mms.OutgoingMediaMessage;
 import org.thoughtcrime.securesms.mms.PartAuthority;
 import org.thoughtcrime.securesms.notifications.MessageNotifier;
@@ -201,7 +198,8 @@ public abstract class PushSendJob extends SendJob {
                                                 Optional.fromNullable(attachment.getDigest()),
                                                 Optional.fromNullable(attachment.getFileName()),
                                                 attachment.isVoiceNote(),
-                                                Optional.fromNullable(attachment.getCaption()));
+                                                Optional.fromNullable(attachment.getCaption()),
+                                                Optional.fromNullable(attachment.getBlurHash()).transform(BlurHash::getHash));
     } catch (IOException | ArithmeticException e) {
       Log.w(TAG, e);
       return null;

src/org/thoughtcrime/securesms/linkpreview/LinkPreviewRepository.java

@@ -12,6 +12,7 @@ import com.bumptech.glide.request.FutureTarget;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
 import org.thoughtcrime.securesms.giph.model.ChunkedImageUrl;
@@ -174,6 +175,7 @@ public class LinkPreviewRepository {
                                                                        false,
                                                                        false,
                                                                        null,
+                                                                       null,
                                                                        null));
 
         callback.onComplete(thumbnail);
@@ -246,6 +248,7 @@ public class LinkPreviewRepository {
                                                        false,
                                                        false,
                                                        null,
+                                                       null,
                                                        null));
 
           callback.onComplete(Optional.of(new LinkPreview(packUrl, title, thumbnail)));

src/org/thoughtcrime/securesms/mediasend/MediaSendActivity.java

@@ -36,6 +36,7 @@ import org.thoughtcrime.securesms.PassphraseRequiredActionBarActivity;
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.TransportOption;
 import org.thoughtcrime.securesms.TransportOptions;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.components.ComposeText;
 import org.thoughtcrime.securesms.components.InputAwareLayout;
 import org.thoughtcrime.securesms.components.SendButton;
@@ -966,7 +967,7 @@ public class MediaSendActivity extends PassphraseRequiredActionBarActivity imple
       } else if (MediaUtil.isGif(mediaItem.getMimeType())) {
         slideDeck.addSlide(new GifSlide(this, mediaItem.getUri(), 0, mediaItem.getWidth(), mediaItem.getHeight(), mediaItem.getCaption().orNull()));
       } else if (MediaUtil.isImageType(mediaItem.getMimeType())) {
-        slideDeck.addSlide(new ImageSlide(this, mediaItem.getUri(), 0, mediaItem.getWidth(), mediaItem.getHeight(), mediaItem.getCaption().orNull()));
+        slideDeck.addSlide(new ImageSlide(this, mediaItem.getUri(), 0, mediaItem.getWidth(), mediaItem.getHeight(), mediaItem.getCaption().orNull(), null));
       } else {
         Log.w(TAG, "Asked to send an unexpected mimeType: '" + mediaItem.getMimeType() + "'. Skipping.");
       }

src/org/thoughtcrime/securesms/mms/AttachmentManager.java

@@ -44,6 +44,7 @@ import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.TransportOption;
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.color.MaterialColor;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.components.AudioView;
 import org.thoughtcrime.securesms.components.DocumentView;
 import org.thoughtcrime.securesms.components.RemovableEditableMediaView;
@@ -315,7 +316,7 @@ public class AttachmentManager {
             }
 
             Log.d(TAG, "remote slide with size " + fileSize + " took " + (System.currentTimeMillis() - start) + "ms");
-            return mediaType.createSlide(context, uri, fileName, mimeType, fileSize, width, height);
+            return mediaType.createSlide(context, uri, fileName, mimeType, null, fileSize, width, height);
           }
         } finally {
           if (cursor != null) cursor.close();
@@ -325,10 +326,10 @@ public class AttachmentManager {
       }
 
       private @NonNull Slide getManuallyCalculatedSlideInfo(Uri uri, int width, int height) throws IOException {
-        long start      = System.currentTimeMillis();
-        Long mediaSize  = null;
-        String fileName = null;
-        String mimeType = null;
+        long     start     = System.currentTimeMillis();
+        Long     mediaSize = null;
+        String   fileName  = null;
+        String   mimeType  = null;
 
         if (PartAuthority.isLocalUri(uri)) {
           mediaSize = PartAuthority.getAttachmentSize(context, uri);
@@ -351,7 +352,7 @@ public class AttachmentManager {
         }
 
         Log.d(TAG, "local slide with size " + mediaSize + " took " + (System.currentTimeMillis() - start) + "ms");
-        return mediaType.createSlide(context, uri, fileName, mimeType, mediaSize, width, height);
+        return mediaType.createSlide(context, uri, fileName, mimeType, null, mediaSize, width, height);
       }
     }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
 
@@ -525,20 +526,21 @@ public class AttachmentManager {
   public enum MediaType {
     IMAGE, GIF, AUDIO, VIDEO, DOCUMENT, VCARD;
 
-    public @NonNull Slide createSlide(@NonNull  Context context,
-                                      @NonNull  Uri     uri,
-                                      @Nullable String fileName,
-                                      @Nullable String mimeType,
-                                                long    dataSize,
-                                                int     width,
-                                                int     height)
+    public @NonNull Slide createSlide(@NonNull  Context  context,
+                                      @NonNull  Uri      uri,
+                                      @Nullable String   fileName,
+                                      @Nullable String   mimeType,
+                                      @Nullable BlurHash blurHash,
+                                                long     dataSize,
+                                                int      width,
+                                                int      height)
     {
       if (mimeType == null) {
         mimeType = "application/octet-stream";
       }
 
       switch (this) {
-      case IMAGE:    return new ImageSlide(context, uri, dataSize, width, height);
+      case IMAGE:    return new ImageSlide(context, uri, dataSize, width, height, blurHash);
       case GIF:      return new GifSlide(context, uri, dataSize, width, height);
       case AUDIO:    return new AudioSlide(context, uri, dataSize, false);
       case VIDEO:    return new VideoSlide(context, uri, dataSize);

src/org/thoughtcrime/securesms/mms/AudioSlide.java

@@ -26,6 +26,7 @@ import androidx.annotation.Nullable;
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.util.MediaUtil;
 import org.thoughtcrime.securesms.util.ResUtil;
@@ -34,11 +35,11 @@ import org.thoughtcrime.securesms.util.ResUtil;
 public class AudioSlide extends Slide {
 
   public AudioSlide(Context context, Uri uri, long dataSize, boolean voiceNote) {
-    super(context, constructAttachmentFromUri(context, uri, MediaUtil.AUDIO_UNSPECIFIED, dataSize, 0, 0, false, null, null, null, voiceNote, false));
+    super(context, constructAttachmentFromUri(context, uri, MediaUtil.AUDIO_UNSPECIFIED, dataSize, 0, 0, false, null, null, null, null, voiceNote, false));
   }
 
   public AudioSlide(Context context, Uri uri, long dataSize, String contentType, boolean voiceNote) {
-    super(context,  new UriAttachment(uri, null, contentType, AttachmentDatabase.TRANSFER_PROGRESS_STARTED, dataSize, 0, 0, null, null, voiceNote, false, null, null));
+    super(context,  new UriAttachment(uri, null, contentType, AttachmentDatabase.TRANSFER_PROGRESS_STARTED, dataSize, 0, 0, null, null, voiceNote, false, null, null, null));
   }
 
   public AudioSlide(Context context, Attachment attachment) {

src/org/thoughtcrime/securesms/mms/DocumentSlide.java

@@ -7,6 +7,7 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.util.StorageUtil;
 
 public class DocumentSlide extends Slide {
@@ -19,7 +20,7 @@ public class DocumentSlide extends Slide {
                        @NonNull String contentType,  long size,
                        @Nullable String fileName)
   {
-    super(context, constructAttachmentFromUri(context, uri, contentType, size, 0, 0, true, StorageUtil.getCleanFileName(fileName), null, null, false, false));
+    super(context, constructAttachmentFromUri(context, uri, contentType, size, 0, 0, true, StorageUtil.getCleanFileName(fileName), null, null, null, false, false));
   }
 
   @Override

src/org/thoughtcrime/securesms/mms/GifSlide.java

@@ -5,6 +5,7 @@ import android.net.Uri;
 import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.util.MediaUtil;
 
 public class GifSlide extends ImageSlide {
@@ -19,7 +20,7 @@ public class GifSlide extends ImageSlide {
   }
 
   public GifSlide(Context context, Uri uri, long size, int width, int height, @Nullable String caption) {
-    super(context, constructAttachmentFromUri(context, uri, MediaUtil.IMAGE_GIF, size, width, height, true, null, caption, null, false, false));
+    super(context, constructAttachmentFromUri(context, uri, MediaUtil.IMAGE_GIF, size, width, height, true, null, caption, null, null, false, false));
   }
 
   @Override

src/org/thoughtcrime/securesms/mms/ImageSlide.java

@@ -25,6 +25,7 @@ import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.attachments.Attachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.util.MediaUtil;
 
 public class ImageSlide extends Slide {
@@ -36,12 +37,12 @@ public class ImageSlide extends Slide {
     super(context, attachment);
   }
 
-  public ImageSlide(Context context, Uri uri, long size, int width, int height) {
-    this(context, uri, size, width, height, null);
+  public ImageSlide(Context context, Uri uri, long size, int width, int height, @Nullable BlurHash blurHash) {
+    this(context, uri, size, width, height, null, blurHash);
   }
 
-  public ImageSlide(Context context, Uri uri, long size, int width, int height, @Nullable String caption) {
-    super(context, constructAttachmentFromUri(context, uri, MediaUtil.IMAGE_JPEG, size, width, height, true, null, caption, null, false, false));
+  public ImageSlide(Context context, Uri uri, long size, int width, int height, @Nullable String caption, @Nullable BlurHash blurHash) {
+    super(context, constructAttachmentFromUri(context, uri, MediaUtil.IMAGE_JPEG, size, width, height, true, null, caption, null, blurHash, false, false));
   }
 
   @Override
@@ -59,6 +60,11 @@ public class ImageSlide extends Slide {
     return true;
   }
 
+  @Override
+  public boolean hasPlaceholder() {
+    return getPlaceholderBlur() != null;
+  }
+
   @NonNull
   @Override
   public String getContentDescription() {

src/org/thoughtcrime/securesms/mms/LocationSlide.java

@@ -14,7 +14,7 @@ public class LocationSlide extends ImageSlide {
 
   public LocationSlide(@NonNull  Context context, @NonNull  Uri uri, long size, @NonNull SignalPlace place)
   {
-    super(context, uri, size, 0, 0);
+    super(context, uri, size, 0, 0, null);
     this.place = place;
   }
 

src/org/thoughtcrime/securesms/mms/PartAuthority.java

@@ -9,6 +9,7 @@ import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.AttachmentId;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.providers.BlobProvider;
 import org.thoughtcrime.securesms.providers.DeprecatedPersistentBlobProvider;

src/org/thoughtcrime/securesms/mms/SignalGlideModule.java

@@ -20,6 +20,9 @@ import com.bumptech.glide.load.resource.gif.GifDrawable;
 import com.bumptech.glide.load.resource.gif.StreamGifDecoder;
 import com.bumptech.glide.module.AppGlideModule;
 
+import org.thoughtcrime.securesms.blurhash.BlurHash;
+import org.thoughtcrime.securesms.blurhash.BlurHashModelLoader;
+import org.thoughtcrime.securesms.blurhash.BlurHashResourceDecoder;
 import org.thoughtcrime.securesms.contacts.avatars.ContactPhoto;
 import org.thoughtcrime.securesms.crypto.AttachmentSecret;
 import org.thoughtcrime.securesms.crypto.AttachmentSecretProvider;
@@ -64,6 +67,8 @@ public class SignalGlideModule extends AppGlideModule {
     registry.prepend(File.class, Bitmap.class, new EncryptedBitmapCacheDecoder(secret, new StreamBitmapDecoder(new Downsampler(registry.getImageHeaderParsers(), context.getResources().getDisplayMetrics(), glide.getBitmapPool(), glide.getArrayPool()), glide.getArrayPool())));
     registry.prepend(File.class, GifDrawable.class, new EncryptedGifCacheDecoder(secret, new StreamGifDecoder(registry.getImageHeaderParsers(), new ByteBufferGifDecoder(context, registry.getImageHeaderParsers(), glide.getBitmapPool(), glide.getArrayPool()), glide.getArrayPool())));
 
+    registry.prepend(BlurHash.class, Bitmap.class, new BlurHashResourceDecoder());
+
     registry.prepend(Bitmap.class, new EncryptedBitmapResourceEncoder(secret));
     registry.prepend(GifDrawable.class, new EncryptedGifDrawableResourceEncoder(secret));
 
@@ -72,6 +77,7 @@ public class SignalGlideModule extends AppGlideModule {
     registry.append(AttachmentModel.class, InputStream.class, new AttachmentStreamUriLoader.Factory());
     registry.append(ChunkedImageUrl.class, InputStream.class, new ChunkedImageUrlLoader.Factory());
     registry.append(StickerRemoteUri.class, InputStream.class, new StickerRemoteUriLoader.Factory());
+    registry.append(BlurHash.class, BlurHash.class, new BlurHashModelLoader.Factory());
     registry.replace(GlideUrl.class, InputStream.class, new OkHttpUrlLoader.Factory());
   }
 

src/org/thoughtcrime/securesms/mms/Slide.java

@@ -25,6 +25,7 @@ import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.attachments.UriAttachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.database.AttachmentDatabase;
 import org.thoughtcrime.securesms.stickers.StickerLocator;
 import org.thoughtcrime.securesms.util.MediaUtil;
@@ -126,6 +127,10 @@ public abstract class Slide {
     throw new AssertionError("getPlaceholderRes() called for non-drawable slide");
   }
 
+  public @Nullable BlurHash getPlaceholderBlur() {
+    return attachment.getBlurHash();
+  }
+
   public boolean hasPlaceholder() {
     return false;
   }
@@ -144,6 +149,7 @@ public abstract class Slide {
                                                          @Nullable String         fileName,
                                                          @Nullable String         caption,
                                                          @Nullable StickerLocator stickerLocator,
+                                                         @Nullable BlurHash       blurHash,
                                                                    boolean        voiceNote,
                                                                    boolean        quote)
   {
@@ -161,7 +167,8 @@ public abstract class Slide {
                              voiceNote,
                              quote,
                              caption,
-                             stickerLocator);
+                             stickerLocator,
+                             blurHash);
   }
 
   @Override

src/org/thoughtcrime/securesms/mms/StickerSlide.java

@@ -9,6 +9,7 @@ import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.attachments.Attachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.stickers.StickerLocator;
 import org.thoughtcrime.securesms.util.MediaUtil;
 
@@ -22,7 +23,7 @@ public class StickerSlide extends Slide {
   }
 
   public StickerSlide(Context context, Uri uri, long size, @NonNull StickerLocator stickerLocator) {
-    super(context, constructAttachmentFromUri(context, uri, MediaUtil.IMAGE_WEBP, size, WIDTH, HEIGHT, true, null, null, stickerLocator, false, false));
+    super(context, constructAttachmentFromUri(context, uri, MediaUtil.IMAGE_WEBP, size, WIDTH, HEIGHT, true, null, null, stickerLocator, null, false, false));
   }
 
   @Override

src/org/thoughtcrime/securesms/mms/TextSlide.java

@@ -7,6 +7,7 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.util.MediaUtil;
 
 public class TextSlide extends Slide {
@@ -16,6 +17,6 @@ public class TextSlide extends Slide {
   }
 
   public TextSlide(@NonNull Context context, @NonNull Uri uri, @Nullable String filename, long size) {
-    super(context, constructAttachmentFromUri(context, uri, MediaUtil.LONG_TEXT, size, 0, 0, true, filename, null, null, false, false));
+    super(context, constructAttachmentFromUri(context, uri, MediaUtil.LONG_TEXT, size, 0, 0, true, filename, null, null, null, false, false));
   }
 }

src/org/thoughtcrime/securesms/mms/VideoSlide.java

@@ -25,6 +25,7 @@ import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.attachments.Attachment;
+import org.thoughtcrime.securesms.blurhash.BlurHash;
 import org.thoughtcrime.securesms.util.MediaUtil;
 import org.thoughtcrime.securesms.util.ResUtil;
 
@@ -35,7 +36,7 @@ public class VideoSlide extends Slide {
   }
 
   public VideoSlide(Context context, Uri uri, long dataSize, @Nullable String caption) {
-    super(context, constructAttachmentFromUri(context, uri, MediaUtil.VIDEO_UNSPECIFIED, dataSize, 0, 0, MediaUtil.hasVideoThumbnail(uri), null, caption, null, false, false));
+    super(context, constructAttachmentFromUri(context, uri, MediaUtil.VIDEO_UNSPECIFIED, dataSize, 0, 0, MediaUtil.hasVideoThumbnail(uri), null, caption, null, null, false, false));
   }
 
   public VideoSlide(Context context, Attachment attachment) {

witness-verifications.gradle

@@ -126,8 +126,8 @@ dependencyVerification {
         'org.whispersystems:curve25519-java:0aadd43cf01d11e9b58f867b3c4f25c3194e8b0623d1953d32dfbfbee009e38d',
         'org.whispersystems:signal-protocol-android:c80aac5f93114da2810e2e89437831f79fcbc8bece652f64aeab313a651cba85',
         'org.whispersystems:signal-protocol-java:7f6df67a963acbab7716424b01b12fa7279f18a9623a2a7c8ba7b1c285830168',
-        'org.whispersystems:signal-service-android:893d42dfa6d08fc1268c4da5aee6f6f3f1bb683ad4a241ef2f3e3d4dfb114e47',
-        'org.whispersystems:signal-service-java:045026003e2ddef0325fe1e930de9ce503010aec8e8a8ac6ddbdd9a79f94e878',
+        'org.whispersystems:signal-service-android:e0a85fa937f7ad0a446ea65405204ab69533339a78d3aa098921cf43c7997348',
+        'org.whispersystems:signal-service-java:5d833e946dbbfb7b4f5dbcf26c1585376e92645aa2958503047ee7a17357897f',
         'pl.tajchert:waitingdots:2835d49e0787dbcb606c5a60021ced66578503b1e9fddcd7a5ef0cd5f095ba2c',
         'se.emilsjolander:stickylistheaders:a08ca948aa6b220f09d82f16bbbac395f6b78897e9eeac6a9f0b0ba755928eeb',
     ]