[FFmpeg-devel] [PATCH] hevc - fix split function of parser

Ståle Kristoffersen staalebk at ifi.uio.no
Fri Sep 25 14:46:42 CEST 2015

On 2015-09-01 at 16:27, Rainer Hochecker wrote:
> fix splitting extradata from ts

this commit introduces a regression for me.
I'm trying to extract a thumb from the middle of a live TS, containing one
Unfortunately I'm not sure if I can provide a sample, but before this patch
I would always get a good looking thumb, but with this patch I would for
the most part get a mostly gray frame.

If I generates a few more thumbnails i see that it eventually spits out the
same frame that ffmpeg before this patch produced as the first thumb, and
it looks OK.

However it is much more blocky than what the previous ffmpeg produced:
This is the command I want to run:

ffmpeg -nostdin -y -an -i hevc_fail.ts -vframes 1 -vf scale=iw*sar:ih thumb%d.jpg -v 100

Before this patch:

with this patch:

If i let it generates a few more thumbs I end up with a "good" thumb: 

However, if you compare the two you will see that even the good thumb with
this patch is much more blocky.

Ståle Kristoffersen

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