commit 0c1407f79ef36422330c2003a608d37df714256b
author Chong Zhang <chz@google.com> Wed May 02 17:09:05 2018 -0700
committer Chong Zhang <chz@google.com> Mon May 07 19:38:05 2018 -0700
tree 04eb9f45da49543f2ad97040a692ea245f8906bd
parent 0c1f9148ed187a9c3819374050c5ea319b059439

Decode one row of tiles at a time for image that has tiles

Add an api to IMediaMetadataRetriever to decode image rect.
It will reuse the same full frame IMemory, and decode only
the requested rect. For now, StagefrightMetadataRetriever
will only allow decoding of rect that's a full row of tiles,
and the requested must be issued sequentially (i.e. no
arbitrary rects). When the extract side is fixed to allow
seeking by tiles, it can be extended to allow arbitrary
rects.

This allows HeifDecoderImpl (on client side) to start
processing the getScanlines in parallel with the decoding.

Test: CTS MediaMetadataRetrieverTest;
Manual testing of HEIF decoding of files with or without tiles;
Manual testing of HEIF thumbnails generation in Downloads app.

bug: 78475896
Change-Id: I820b21cdf33f80593ee6092d8e1ba68b3beb65dd

media/libmediaplayerservice/MetadataRetrieverClient.cpp

diff --git a/media/libmediaplayerservice/MetadataRetrieverClient.cpp b/media/libmediaplayerservice/MetadataRetrieverClient.cpp
index fa41c06..40b17bf 100644
--- a/media/libmediaplayerservice/MetadataRetrieverClient.cpp
+++ b/media/libmediaplayerservice/MetadataRetrieverClient.cpp
@@ -213,7 +213,7 @@
 
 sp<IMemory> MetadataRetrieverClient::getImageAtIndex(
         int index, int colorFormat, bool metaOnly, bool thumbnail) {
-    ALOGV("getFrameAtTime: index(%d) colorFormat(%d), metaOnly(%d) thumbnail(%d)",
+    ALOGV("getImageAtIndex: index(%d) colorFormat(%d), metaOnly(%d) thumbnail(%d)",
             index, colorFormat, metaOnly, thumbnail);
     Mutex::Autolock lock(mLock);
     Mutex::Autolock glock(sLock);
@@ -229,6 +229,25 @@
     return frame;
 }
 
+sp<IMemory> MetadataRetrieverClient::getImageRectAtIndex(
+        int index, int colorFormat, int left, int top, int right, int bottom) {
+    ALOGV("getImageRectAtIndex: index(%d) colorFormat(%d), rect {%d, %d, %d, %d}",
+            index, colorFormat, left, top, right, bottom);
+    Mutex::Autolock lock(mLock);
+    Mutex::Autolock glock(sLock);
+    if (mRetriever == NULL) {
+        ALOGE("retriever is not initialized");
+        return NULL;
+    }
+    sp<IMemory> frame = mRetriever->getImageRectAtIndex(
+            index, colorFormat, left, top, right, bottom);
+    if (frame == NULL) {
+        ALOGE("failed to extract image");
+        return NULL;
+    }
+    return frame;
+}
+
 status_t MetadataRetrieverClient::getFrameAtIndex(
             std::vector<sp<IMemory> > *frames,
             int frameIndex, int numFrames, int colorFormat, bool metaOnly) {