Java 类com.bumptech.glide.load.resource.bitmap.Downsampler 实例源码

private static <T> Bitmap createScaledBitmapInto(Context context, T model, int width, int height)
    throws BitmapDecodingException
{
  final Bitmap rough = Downsampler.AT_LEAST.decode(getInputStreamForModel(context, model),
                                                   Glide.get(context).getBitmapPool(),
                                                   width, height,
                                                   DecodeFormat.PREFER_RGB_565);

  final Resource<Bitmap> resource = BitmapResource.obtain(rough, Glide.get(context).getBitmapPool());
  final Resource<Bitmap> result   = new FitCenter(context).transform(resource, width, height);

  if (result == null) {
    throw new BitmapDecodingException("unable to transform Bitmap");
  }
  return result.get();
}

private static <T> Bitmap createScaledBitmapInto(Context context, T model,
        int width, int height)
        throws BitmapDecodingException {
    final Bitmap rough = Downsampler.AT_LEAST
            .decode(getInputStreamForModel(context, model),
                    Glide.get(context).getBitmapPool(),
                    width, height, DecodeFormat.PREFER_RGB_565);

    final Resource<Bitmap> resource = BitmapResource
            .obtain(rough, Glide.get(context).getBitmapPool());
    final Resource<Bitmap> result =
            new FitCenter(context).transform(resource, width, height);

    if (result == null) {
        throw new BitmapDecodingException("unable to transform Bitmap");
    }
    return result.get();
}

private static <T> Bitmap createScaledBitmapInto(Context context, T model,
        int width, int height)
        throws BitmapDecodingException {
    final Bitmap rough = Downsampler.AT_LEAST
            .decode(getInputStreamForModel(context, model),
                    Glide.get(context).getBitmapPool(),
                    width, height, DecodeFormat.PREFER_RGB_565);

    final Resource<Bitmap> resource = BitmapResource
            .obtain(rough, Glide.get(context).getBitmapPool());
    final Resource<Bitmap> result =
            new FitCenter(context).transform(resource, width, height);

    if (result == null) {
        throw new BitmapDecodingException("unable to transform Bitmap");
    }
    return result.get();
}

private static <T> Bitmap createScaledBitmapInto(Context context, T model, int width, int height)
    throws BitmapDecodingException
{
  final Bitmap rough = Downsampler.AT_LEAST.decode(getInputStreamForModel(context, model),
                                                   Glide.get(context).getBitmapPool(),
                                                   width, height,
                                                   DecodeFormat.PREFER_RGB_565);

  final Resource<Bitmap> resource = BitmapResource.obtain(rough, Glide.get(context).getBitmapPool());
  final Resource<Bitmap> result   = new FitCenter(context).transform(resource, width, height);

  if (result == null) {
    throw new BitmapDecodingException("unable to transform Bitmap");
  }
  return result.get();
}

private static <T> Bitmap createScaledBitmapInto(Context context, T model, int width, int height)
    throws BitmapDecodingException
{
  final Bitmap rough = Downsampler.AT_LEAST.decode(getInputStreamForModel(context, model),
                                                   Glide.get(context).getBitmapPool(),
                                                   width, height,
                                                   DecodeFormat.PREFER_RGB_565);

  final Resource<Bitmap> resource = BitmapResource.obtain(rough, Glide.get(context).getBitmapPool());
  final Resource<Bitmap> result   = new FitCenter(context).transform(resource, width, height);

  if (result == null) {
    throw new BitmapDecodingException("unable to transform Bitmap");
  }
  return result.get();
}

public static <T> byte[] createScaledBytes(Context context, T model, MediaConstraints constraints)
    throws BitmapDecodingException
{
  int    quality  = MAX_COMPRESSION_QUALITY;
  int    attempts = 0;
  byte[] bytes;

  Bitmap scaledBitmap =  Downsampler.AT_MOST.decode(getInputStreamForModel(context, model),
                                                    Glide.get(context).getBitmapPool(),
                                                    constraints.getImageMaxWidth(context),
                                                    constraints.getImageMaxHeight(context),
                                                    DecodeFormat.PREFER_RGB_565);

  if (scaledBitmap == null) {
    throw new BitmapDecodingException("Unable to decode image");
  }

  try {
    do {
      ByteArrayOutputStream baos = new ByteArrayOutputStream();
      scaledBitmap.compress(CompressFormat.JPEG, quality, baos);
      bytes = baos.toByteArray();

      Log.w(TAG, "iteration with quality " + quality + " size " + (bytes.length / 1024) + "kb");
      if (quality == MIN_COMPRESSION_QUALITY) break;

      int nextQuality = (int)Math.floor(quality * Math.sqrt((double)constraints.getImageMaxSize() / bytes.length));
      if (quality - nextQuality < MIN_COMPRESSION_QUALITY_DECREASE) {
        nextQuality = quality - MIN_COMPRESSION_QUALITY_DECREASE;
      }
      quality = Math.max(nextQuality, MIN_COMPRESSION_QUALITY);
    }
    while (bytes.length > constraints.getImageMaxSize() && attempts++ < MAX_COMPRESSION_ATTEMPTS);
    if (bytes.length > constraints.getImageMaxSize()) {
      throw new BitmapDecodingException("Unable to scale image below: " + bytes.length);
    }
    Log.w(TAG, "createScaledBytes(" + model.toString() + ") -> quality " + Math.min(quality, MAX_COMPRESSION_QUALITY) + ", " + attempts + " attempt(s)");
    return bytes;
  } finally {
    if (scaledBitmap != null) scaledBitmap.recycle();
  }
}

public static <T> byte[] createScaledBytes(Context context, T model, MediaConstraints constraints)
    throws BitmapDecodingException
{
  int    quality  = MAX_COMPRESSION_QUALITY;
  int    attempts = 0;
  byte[] bytes;

  Bitmap scaledBitmap =  Downsampler.AT_MOST.decode(getInputStreamForModel(context, model),
                                                    Glide.get(context).getBitmapPool(),
                                                    constraints.getImageMaxWidth(context),
                                                    constraints.getImageMaxHeight(context),
                                                    DecodeFormat.PREFER_RGB_565);

  if (scaledBitmap == null) {
    throw new BitmapDecodingException("Unable to decode image");
  }

  try {
    do {
      ByteArrayOutputStream baos = new ByteArrayOutputStream();
      scaledBitmap.compress(CompressFormat.JPEG, quality, baos);
      bytes = baos.toByteArray();

      Log.w(TAG, "iteration with quality " + quality + " size " + (bytes.length / 1024) + "kb");
      if (quality == MIN_COMPRESSION_QUALITY) break;

      int nextQuality = (int)Math.floor(quality * Math.sqrt((double)constraints.getImageMaxSize(context) / bytes.length));
      if (quality - nextQuality < MIN_COMPRESSION_QUALITY_DECREASE) {
        nextQuality = quality - MIN_COMPRESSION_QUALITY_DECREASE;
      }
      quality = Math.max(nextQuality, MIN_COMPRESSION_QUALITY);
    }
    while (bytes.length > constraints.getImageMaxSize(context) && attempts++ < MAX_COMPRESSION_ATTEMPTS);
    if (bytes.length > constraints.getImageMaxSize(context)) {
      throw new BitmapDecodingException("Unable to scale image below: " + bytes.length);
    }
    Log.w(TAG, "createScaledBytes(" + model.toString() + ") -> quality " + Math.min(quality, MAX_COMPRESSION_QUALITY) + ", " + attempts + " attempt(s)");
    return bytes;
  } finally {
    if (scaledBitmap != null) scaledBitmap.recycle();
  }
}

public static <T> byte[] createScaledBytes(Context context, T model, MediaConstraints constraints)
    throws BitmapDecodingException
{
  int    quality  = MAX_COMPRESSION_QUALITY;
  int    attempts = 0;
  byte[] bytes;

  Bitmap scaledBitmap =  Downsampler.AT_MOST.decode(getInputStreamForModel(context, model),
                                                    Glide.get(context).getBitmapPool(),
                                                    constraints.getImageMaxWidth(context),
                                                    constraints.getImageMaxHeight(context),
                                                    DecodeFormat.PREFER_RGB_565);

  if (scaledBitmap == null) {
    throw new BitmapDecodingException("Unable to decode image");
  }

  try {
    do {
      ByteArrayOutputStream baos = new ByteArrayOutputStream();
      scaledBitmap.compress(CompressFormat.JPEG, quality, baos);
      bytes = baos.toByteArray();

      Log.w(TAG, "iteration with quality " + quality + " size " + (bytes.length / 1024) + "kb");
      if (quality == MIN_COMPRESSION_QUALITY) break;

      int nextQuality = (int)Math.floor(quality * Math.sqrt((double)constraints.getImageMaxSize() / bytes.length));
      if (quality - nextQuality < MIN_COMPRESSION_QUALITY_DECREASE) {
        nextQuality = quality - MIN_COMPRESSION_QUALITY_DECREASE;
      }
      quality = Math.max(nextQuality, MIN_COMPRESSION_QUALITY);
    }
    while (bytes.length > constraints.getImageMaxSize() && attempts++ < MAX_COMPRESSION_ATTEMPTS);
    if (bytes.length > constraints.getImageMaxSize()) {
      throw new BitmapDecodingException("Unable to scale image below: " + bytes.length);
    }
    Log.w(TAG, "createScaledBytes(" + model.toString() + ") -> quality " + Math.min(quality, MAX_COMPRESSION_QUALITY) + ", " + attempts + " attempt(s)");
    return bytes;
  } finally {
    if (scaledBitmap != null) scaledBitmap.recycle();
  }
}

/**
 * Load images using the given {@link Downsampler}. Replaces any existing image decoder. Defaults to
 * {@link Downsampler#AT_LEAST}. Will be ignored if the data represented by the model is a video. This replaces any
 * previous calls to {@link #imageDecoder(ResourceDecoder)}  and {@link #decoder(ResourceDecoder)} with default
 * decoders with the appropriate options set.
 *
 * @see #imageDecoder
 *
 * @param downsampler The downsampler
 * @return This RequestBuilder
 */
private BitmapRequestBuilder<ModelType, TranscodeType> downsample(Downsampler downsampler) {
    this.downsampler = downsampler;
    imageDecoder = new StreamBitmapDecoder(downsampler, bitmapPool, decodeFormat);
    super.decoder(new ImageVideoBitmapDecoder(imageDecoder, videoDecoder));
    return this;
}

/**
 * Load images using the given {@link Downsampler}. Replaces any existing image decoder. Defaults to
 * {@link Downsampler#AT_LEAST}. Will be ignored if the data represented by the model is a video. This replaces any
 * previous calls to {@link #imageDecoder(ResourceDecoder)}  and {@link #decoder(ResourceDecoder)} with default
 * decoders with the appropriate options set.
 *
 * @see #imageDecoder
 *
 * @param downsampler The downsampler
 * @return This RequestBuilder
 */
private BitmapRequestBuilder<ModelType, TranscodeType> downsample(Downsampler downsampler) {
    this.downsampler = downsampler;
    imageDecoder = new StreamBitmapDecoder(downsampler, bitmapPool, decodeFormat);
    super.decoder(new ImageVideoBitmapDecoder(imageDecoder, videoDecoder));
    return this;
}

/**
 * Load images using the given {@link Downsampler}. Replaces any existing image decoder. Defaults to
 * {@link Downsampler#AT_LEAST}. Will be ignored if the data represented by the model is a video. This replaces any
 * previous calls to {@link #imageDecoder(ResourceDecoder)}  and {@link #decoder(ResourceDecoder)} with default
 * decoders with the appropriate options set.
 *
 * @see #imageDecoder
 *
 * @param downsampler The downsampler
 * @return This RequestBuilder
 */
private BitmapRequestBuilder<ModelType, TranscodeType> downsample(Downsampler downsampler) {
    this.downsampler = downsampler;
    imageDecoder = new StreamBitmapDecoder(downsampler, bitmapPool, decodeFormat);
    super.decoder(new ImageVideoBitmapDecoder(imageDecoder, videoDecoder));
    return this;
}

/**
 * Load images using the given {@link Downsampler}. Replaces any existing image decoder. Defaults to
 * {@link Downsampler#AT_LEAST}. Will be ignored if the data represented by the model is a video. This replaces any
 * previous calls to {@link #imageDecoder(ResourceDecoder)}  and {@link #decoder(ResourceDecoder)} with default
 * decoders with the appropriate options set.
 *
 * @see #imageDecoder
 *
 * @param downsampler The downsampler
 * @return This RequestBuilder
 */
private BitmapRequestBuilder<ModelType, TranscodeType> downsample(Downsampler downsampler) {
    this.downsampler = downsampler;
    imageDecoder = new StreamBitmapDecoder(downsampler, bitmapPool, decodeFormat);
    super.decoder(new ImageVideoBitmapDecoder(imageDecoder, videoDecoder));
    return this;
}

/**
 * Sets the {@link DownsampleStrategy} to use when decoding {@link Bitmap Bitmaps} using
 * {@link Downsampler}.
 */
public RequestOptions downsample(@NonNull DownsampleStrategy strategy) {
  return set(Downsampler.DOWNSAMPLE_STRATEGY, Preconditions.checkNotNull(strategy));
}

/**
 * Disables the use of {@link android.graphics.Bitmap.Config#HARDWARE} in {@link Downsampler} to
 * avoid errors caused by inspecting Bitmap pixels, drawing with hardware support disabled,
 * drawing to {@link android.graphics.Canvas}s backed by {@link Bitmap}s etc.
 *
 * <p>It's almost never safe to set {@link Downsampler#ALLOW_HARDWARE_CONFIG} to {@code true} so
 * we only provide a way to disable hardware configs entirely. If no option is set for
 * {@link Downsampler#ALLOW_HARDWARE_CONFIG}, Glide will set the value per request based on
 * whether or not a {@link Transformation} is applied and if one is, the type of
 * {@link Transformation} applied. Built in transformations like {@link FitCenter} and
 * {@link com.bumptech.glide.load.resource.bitmap.DownsampleStrategy.CenterOutside} can safely use
 * {@link android.graphics.Bitmap.Config#HARDWARE} because they can be entirely replaced by
 * scaling within {@link Downsampler}. {@link Transformation}s like {@link #circleCrop()} that
 * can't be replicated by {@link Downsampler} cannot use {@link Bitmap.Config#HARDWARE} because
 * {@link android.graphics.Bitmap.Config#HARDWARE} cannot be drawn to
 * {@link android.graphics.Canvas}s, which is required by most {@link Transformation}s.
 */
@CheckResult
public RequestOptions disallowHardwareConfig() {
  return set(Downsampler.ALLOW_HARDWARE_CONFIG, false);
}

/**
 * Sets the {@link DownsampleStrategy} to use when decoding {@link Bitmap Bitmaps} using
 * {@link Downsampler}.
 *
 * <p>This is a component option specific to {@link Downsampler}. If the defautlt Bitmap decoder
 * is replaced or skipped because of your configuration, this option may be ignored.
 */
@CheckResult
public RequestOptions downsample(@NonNull DownsampleStrategy strategy) {
  return set(Downsampler.DOWNSAMPLE_STRATEGY, Preconditions.checkNotNull(strategy));
}

/**
 * Load images at a size near the size of the target using {@link Downsampler#AT_LEAST}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> approximate() {
    return downsample(Downsampler.AT_LEAST);
}

/**
 * Load images at their original size using {@link Downsampler#NONE}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> asIs() {
    return downsample(Downsampler.NONE);
}

/**
 * Load images at a size near the size of the target using {@link Downsampler#AT_LEAST}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> approximate() {
    return downsample(Downsampler.AT_LEAST);
}

/**
 * Load images at their original size using {@link Downsampler#NONE}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> asIs() {
    return downsample(Downsampler.NONE);
}

/**
 * Load images at a size near the size of the target using {@link Downsampler#AT_LEAST}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> approximate() {
    return downsample(Downsampler.AT_LEAST);
}

/**
 * Load images at their original size using {@link Downsampler#NONE}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> asIs() {
    return downsample(Downsampler.NONE);
}

/**
 * Load images at a size near the size of the target using {@link Downsampler#AT_LEAST}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> approximate() {
    return downsample(Downsampler.AT_LEAST);
}

/**
 * Load images at their original size using {@link Downsampler#NONE}.
 *
 * @see #downsample(Downsampler)
 *
 * @return This RequestBuilder
 */
public BitmapRequestBuilder<ModelType, TranscodeType> asIs() {
    return downsample(Downsampler.NONE);
}