H.264 decoding glitches on A7 and A8 devices

Originator:matej.knopp
Number:rdar://18597194 Date Originated:09-Oct-2014
Status:Open Resolved:
Product:iOS Product Version:7,8,8.1
Classification:Bug Reproducible:Always
 
Playing H.264 stream encoded by VideoToolbox on MacBook Air shows decoding glitches.

The H.264 stream was encoded using VideoToolbox H.264 encoder on 2012 MacBook Air (using hardware encoder). Bitrate, profile and keyframe interval was not specified, but the issue persists regardless of encoder settings.

Older devices (pre-A7), desktop, Apple TV and software decoders have no trouble decoding the stream (regardless of firmware version).
 
A7 and A8 decoders show glitches (tested with iPad Air 8.1-beta and iPhone 6+ 8.0.1).

Steps to Reproduce:
Sample stream can be found here:

https://s3.amazonaws.com/MatejK/DecodeGlitch/prog_index.m3u8

Opening in Safari on A7 and A8 devices should be enough to reproduce problem

Expected Results:
Video decodes and plays properly

Actual Results:
Video does not decode properly. Screen recording from iPad Air showing the issue:

https://s3.amazonaws.com/MatejK/DecodeGlitch/DecodingGlitch-Demo.mov

Version:
A7 iPad Air with iOS 8.1 (12B401) and iPhone 6+ with iOS 8.0.2 (12A405)

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