This file serves to document some of the decoder errata when using MediaCodec hardware decoders on certain devices. 1. num_ref_frames is set to 16 by NVENC which causes decoders to allocate 16+ buffers. This can cause an error or lag on some devices. - Affected decoders: TI OMAP4, Allwinner A20 2. Some H.264 decoders have a huge per-frame latency with the unmodified SPS sent from NVENC. Setting max_dec_frame_buffering=1 fixes this latency issue. - Affected decoders: NVIDIA Tegra 3 and 4, Broadcom VideoCore IV, MT8176 (HEVC not affected) 3. Some decoders strictly require that you pass BUFFER_FLAG_CODEC_CONFIG and crash upon the IDR frame if you don't - Affected decoders: TI OMAP4 4. Some decoders require num_ref_frames=1 and max_dec_frame_buffering=1 to avoid crashing on SPS on first I-frame - Affected decoders: Qualcomm in GS3 on 4.3+, Exynos 4 at 1080p only 5. Some decoders will hang or crash if max_dec_frame_buffering is not present and level_idc is >= 50 - Affected decoders: MediaTek decoder in Fire HD 6/7 (2014) 6. Some decoders will hang if max_dec_frame_buffering IS present - Affected decoders: Exynos 5 in Galaxy Note 10.1 (2014) 7. Some decoders will not enter low latency mode if adaptive playback is enabled - Affected decoders: Intel decoder in Nexus Player 8. Some decoders will not enter low latency mode if the profile isn't baseline in the first SPS because B-frames may be present. - Affected decoders: Intel decoder in Nexus Player (prior to Android 6.0) 9. Some decoders will not enter low latency mode if the profile isn't constrained high profile because B-frames may be present. - Affected decoders: Intel decoder in Nexus Player (after Android 6.0) 10. Some decoders actually suffer increased latency when max_dec_frame_buffering=1 - Affected decoders: MediaTek decoder in Fire TV 2015 11. Attempting to use reference picture invalidation at 1080p causes the decoder to crash on low-end Snapdragon SoCs. 720p is unaffected. - Affected decoders: Snapdragon 200, 410, 415, 430, 435, 616 12. Enabling adaptive playback causes H.265 1080p and 4K playback to fail on some MediaTek SoCs. - Affected decoders: MT5832 in Sony BRAVIA 4K GB (BRAVIA_ATV2) and MT5890 in Phillips 55PUS6501 13. Some HEVC decoders hang when receiving a stream with 16 reference frames - Affected decoders: Amlogic S905Z in Fire TV 3 14. Some HEVC decoders lag when receiving a stream with 16 reference frames - Affected decoders: Tegra X1 in Pixel C (but NOT in SHIELD TV darcy)