Suvarna1488 / webm

Automatically exported from code.google.com/p/webm
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Using tiles with internal scaling fails #989

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago
Encoding a 720p clip specifying --tile-columns=2 (i.e. 4 tile columns) and 
allowing scaling can cause vpxenc to produce corrupt encoded bitstreams. 
Neither vpxdec nor the Intel VP9 Analyzer tool is able to handle them.

Changing --tile-columns=0 results in valid output streams.

Possible explanation:

Given the minimum size of a tile column (256 pixels) we may have to change the 
number of tiles used to encode a scaled down frame.

e.g. A 720p clip with 75% scaling results in down-scaled frames that are 
960x540. Requesting 4 tile columns for the full-size frame is OK, but is not 
possible for the down-scaled frames.

Command line:

/usr/local/google/home/agrange/clips/derf/y4m_720p/park_joy_420_720p50.y4m
  -o test_debug.webm
  --good
  --cpu-used=5
  --profile=0
  --lag-in-frames=25
  --min-q=0 --max-q=48
  --auto-alt-ref=1  --arnr-maxframes=7 --arnr-strength=5 
  --passes=2
  --pass=2
  --fpf=firstpass_parkjoy720.stt
  --kf-max-dist=9999 --kf-min-dist=0
  --drop-frame=0
  --static-thresh=0
  --bias-pct=50
  --minsection-pct=0 --maxsection-pct=200
  --sharpness=0
  --limit=300
  --undershoot-pct=100
  --end-usage=vbr
  --codec=vp9
  --resize-allowed=1
  --target-bitrate=500
  --tile-columns=2
  --threads=0
  --aq-mode=0

Original issue reported on code.google.com by agra...@google.com on 17 Apr 2015 at 9:36

GoogleCodeExporter commented 9 years ago
Added a call to set_tile_limits in update_frame_size so that the tile 
configuration is re-initialized on any frame size change.

Original comment by agra...@google.com on 20 Apr 2015 at 10:12

GoogleCodeExporter commented 9 years ago

Original comment by agra...@google.com on 20 Apr 2015 at 10:13

GoogleCodeExporter commented 9 years ago
Updated auto-scaling patch with the fix:
https://gerrit.chromium.org/gerrit/#/c/73990/

Original comment by agra...@google.com on 20 Apr 2015 at 10:15