Opened 5 years ago
Closed 3 years ago
#7923 closed defect (fixed)
alpha info is lost during transcode to gif from apng or animated webp
Reported by: | gdh | Owned by: | Elon Musk |
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Priority: | normal | Component: | avfilter |
Version: | git-master | Keywords: | paletteuse |
Cc: | onemda@gmail.com, michael@niedermayer.cc, gbp.gap@gmail.com | Blocked By: | |
Blocking: | Reproduced by developer: | no | |
Analyzed by developer: | no |
Description
Summary of the bug:
How to reproduce:
% ffmpeg -i alpha.apng alpha.gif ffmpeg version N-93899-g1d74150 built on gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-16)
Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.
Attachments (5)
Change History (16)
by , 5 years ago
Attachment: | alpha.apng added |
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comment:1 by , 5 years ago
the issue can be reproduced by the command below:
ffmpeg -i alpha.webp alpha.gif
comment:2 by , 5 years ago
Resolution: | → wontfix |
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Status: | new → closed |
You need to use filters(palettegen, paletteuse) to get it working.
comment:3 by , 5 years ago
Resolution: | wontfix |
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Status: | closed → reopened |
With the command with palettegen,paletteuse as below, the unexpected red boundary lines are produced, which is different with the input apng file alpha.apng
./ffmpeg -i alpha.apng -filter_complex "[0]split[a][b];[a]palettegen[p];[b][p]paletteuse " alpha_pale.gif
comment:4 by , 5 years ago
BTW, please ignore the org_gif.gif which is the same file of alpha.gif. i don't know how to remove it. :(
-Mike
comment:5 by , 5 years ago
More comments:
Richard,
Thanks for your quick reply! your suggestion (palettegen, paletteuse) can remove the background and bring the alpha alive, but it causes some defects (red lines) as described above.
Any suggestion?
-Mike
comment:7 by , 5 years ago
Richard,
Could you merge the bug into the ticket as you mentioned? or provide the link of the ticket you mentioned?
Thanks!
BTW, I tried to change the title of the ticket, but failed. If you need me to submit another for the bug, please let me know.
-Mike
comment:8 by , 5 years ago
Owner: | set to |
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Status: | reopened → open |
comment:9 by , 5 years ago
Component: | avcodec → avfilter |
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Keywords: | paletteuse added; apng gif alpha webp removed |
The red boundaries look like an issue unrelated to gif and apng.
comment:10 by , 5 years ago
Cc: | added |
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It seems to be the same issue with #7902.
https://trac.ffmpeg.org/ticket/7902
-Mike
comment:11 by , 3 years ago
Resolution: | → fixed |
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Status: | open → closed |
input apng file