20:27
I have tried to make a bitstream filter for FFmpeg that drops the nth keyframe for positive numbers and allows the first n keyframes and drops the rest for nonpositive numbers, called "datamosh":
ffmpeg -i input.webm -bsf:v datamosh=target=20 -c copy output.webm
outputs the error:
Option 'target' not found
[vost#0:0/copy ⓐ 0x54edc40] Error parsing bitstream filter sequence 'datamosh=target=20': Option not found
Here is the code for the "datamosh" bitstream filter:
#include "bsf.h"
#include "bsf_internal.h"
#include (...)
15:07
Trying to encode XDCAM HD422 MXF with FFMPEG
But can't know specific setting for encoder/format/mux
Anyone can show me sample code or give some advice for that ?
09:43
So I have a .ts file and a converted .dvb sub file (.SRT TO .DVB) that I want to mux togheter using FFMPEG. The mux is a success and the file plays fine in VLC or other modern divce.However I have an older divce (around 10 yeras old) where playback has issues, whenever a line of subs is displayd the picture and and audio gets corrupted and frezzes up and as sson there are no lins everything looks good again and so on. Note that subs are displayd correctly and they are not affected by the issue, only picture and audio is.
I have tried using diffrent command without any luck but here (...)
07:45
To get a thumbnail from an image halfway through the video I can do ffmpeg -ss 100 -i /tmp/video.mp4 -frames:v 1 -s 200x100 image.jpg. By using -ss 100 it gets a thumbnail at 100 seconds (which would be halfway through the video assuming the video is 200 seconds long).
But if I don't know the exact length of the video, in my application code I would need to use something like ffprobe to first determine the length of the video, and then divide it by 2 to get the thumbnail time.
Is there a way to get ffmpeg to get the thumbnail at the percentage of the video you (...)