ffmpeg - I frame 을 뽑는 방법
http://ffmpeg-users.933282.n4.nabble.com/Extracting-I-Frames-from-Mpeg4-videos-td2952952.html
>> Is there any way to extract I-frames from a mpeg-4 video using ffmpeg ?
- One way to do it would be:
Use FFprobe firstly to determine which frames are I frames and then
extract the frames with -vframes=1 and -ss. Ideally, automate the
process.
- A more elegant solution: add frame-type properties to
AVFilterBufferRef, implement a filter for only outputting I-frames,
and connect this filter to a movie sink.
All this is not yet implemented, but would be a good exercise for
someone which is intereseted into contributing to FFmpeg/libavfilter.
FFmpeg을 이용한 Android 동영상 플레이어 개발 - 그냥 도움이 될까 해서
http://helloworld.naver.com/helloworld/8794
NHN 동영상서비스개발2팀 김대웅
Android 는 오픈 플랫폼이어서 단말기가 제공하는 동영상 플레이어의 기능과 지원하는 포맷이 제조사마다 다릅니다. 그래서 더 효율적으로 동영상 서비스를 제공하려면 독자적인 동영상 플레이어가 있는 것이 좋습니다. 이 글에서는 오픈 소스인 FFmpeg의 레퍼런스 프로젝트인 FFPlay로 Android용 동영상 플레이어를 제작하기까지의 고민과 과정을 소개합니다.
How to hack ffmpeg to consider I-Frames as key frames?
http://stackoverflow.com/questions/8676651/how-to-hack-ffmpeg-to-consider-i-frames-as-key-frames
interace - http://hruj.tistory.com/5
- I'm trying to get ffmpeg to seek h264 interlaced videos, and i found that i can seek to any frame if i just force it.
I already hacked the decode,0ㅜㅐ r to consider I - Frames as keyframes, and it works nicely with the videos i need it to work with. And there will NEVER be any videos encoded with different encoders.
However, i'd like the seek to find me an I - Frame and not just any frame.
What i'd need to do is to hack The AVIndexEntry creation so that it marks any frame that is an I-Frame to be a key frame. Or alternatively, hack the search thing to return I - Frames.
The code does get a tad dfficult to follow at this point.
Can someone please point me at the correct place in ffmpeg code which handles this?
-This isn't possible as far as i can tell..
But if you do know where the I-Frames are, by either decoding the entire video or by just knowing, you can insert stuff into the AVIndexEntry information stored in the stream.
AVIndexEntries have a flag that tells if it's a keyframe, just set it to true on I-Frames.
Luckily, i happen to know where they are in my videos :)
-mika
HANDY TIP: Using FFprobe for stream analysis
http://forums.creativecow.net/thread/291/71
extracting key frames with ffmpeg ******************************* 아주 중요!
http://37rtm.host22.com/content/extracting-key-frames-ffmpeg
Google >> ffmpeg key frame
http://www.google.com/search?client=ubuntu&channel=fs&q=ffmpeg+I+frame&ie=utf-8&oe=utf-8#hl=ko&client=ubuntu&tbo=d&channel=fs&sclient=psy-ab&q=ffmpeg+key+frame&oq=ffmpeg+key+frame&gs_l=serp.3..0i7i10i30l2j0i7i30l2.6491.8714.0.8878.10.8.2.0.0.4.285.1526.0j3j4.7.0...0.0...1c.1.gMcseSKVMwU&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=35c0718840beb598&bpcl=38897761&biw=1301&bih=678
Extract a keyframe from a video with FFMpeg
http://kr3l.wordpress.com/2009/12/03/extract-a-keyframe-from-a-video-with-ffmpeg/
ffmpeg keyframe extraction
http://stackoverflow.com/questions/12538914/ffmpeg-keyframe-extraction
Google >> ffmpeg -vf select="eq(pict_type\,PICT_TYPE_I)"
http://www.google.com/search?client=ubuntu&channel=fs&q=ffmpeg+I+frame&ie=utf-8&oe=utf-8#hl=ko&client=ubuntu&tbo=d&channel=fs&sclient=psy-ab&q=ffmpeg+-vf+select%3D%22eq%28pict_type\%2CPICT_TYPE_I%29%22&oq=ffmpeg+-vf+select%3D%22eq%28pict_type\%2CPICT_TYPE_I%29%22&gs_l=serp.12...863595.863595.1.864751.1.1.0.0.0.0.184.184.0j1.1.0...0.0...1c.1.OhlvWZtOa2s&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=35c0718840beb598&bpcl=38897761&biw=1089&bih=518
FFmpeg-users - Using the "select" filter
http://ffmpeg-users.933282.n4.nabble.com/Using-the-quot-select-quot-filter-td4079651.html
http://ffmpeg.org/ffmpeg.html#select
