Forums - Galaxy S4 and Nexus 4, with Adreno GPUs, crash while encoding from surface with certain contents

I found an error appearing while encoding from a GPU generated surface using the hardware h264 encoder on Galaxy S4. It happens 100% for selected images and device. We could reproduce it with the Grafika software, available on github, developed by Google employees.

Modified version of Grafika renders an image first to a texture, and then the texture is rendered to both display and the encoder surface. For certain images, the encoder crashes when a key frame is following, 100% in the same place. The crash happens sooner if bitrate is increased (for 720p, 7 Mbps determines a crash within the first 3 keyframes). For other images, the crash happens later.

In order to reproduce, in Grafika sofware: https://github.com/google/grafika replace the recordfboactivity with the one attached. (the changes: instead of geometric forms, just render an image to the texture, and increase the bitrate from 4 to 7) The logcat is also attached, and the error. (they are separate as the error fills the logcat very fast). The image should be placed in Movies/android_mediaclips. Start the application, select "Record GL app", turn it in landscape mode, select "Rec: FBO blit x2" and then Start recording. It should freeze after 300 frames. (third key frame - one key frame is generated every 5 seconds in grafika. To change that, check IFRAME_INTERVAL in VideoEncoderCore.java. There could be useful a logcat message to show last data sent to muxer, i.e. after mMuxer.writeSampleData(mTrackIndex, encodedData, mBufferInfo);
put Log.d(TAG, "sent " + mBufferInfo.size + " bytes to muxer, ts=" + mBufferInfo.presentationTimeUs/1000);

I observed that if instead of texture with static image I have an external texture with video, the error does not appear. Also, if I blend the image from frame to frame with a variable texture, the crash is delayed or does not appear. I was thinking that due to very small/no variations from frame to frame, encoded predicted frames are very small, while the intra frames are very large. This might cause issues with bitrate algorithm, or some other problems.

I am not interested in a driver solution, but rather in understanding what goes wrong, and how I can create a workaround so that we can release our application for qualcomm devices too. Grafika was used just to reproduce our issue.