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  1. Member
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    Originally Posted by jagabo View Post
    Code:
     ffmpeg -i src.m2v -vf showinfo -f image2 img%05d.jpg  2>list.txt
    By default, ffmpeg exports jpgs at a very low quality. Add -qscale 1 to the string of commands for the highest quality:
    Code:
    ffmpeg -i src.m2v -vf showinfo -f image2 -qscale 1 img%05d.jpg  2>list.txt
    or export to png instead:
    Code:
    ffmpeg -i src.m2v -vf showinfo -f image2 img%05d.png  2>list.txt
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  2. Yes, and you can easily change the output to PNG or BMP by changing the output filename spec.
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    i treid it and finally i get an output, but the numebr of frames in the text file(n=) not equal the number of jpg files?
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  4. Originally Posted by abeer View Post
    i treid it and finally i get an output, but the numebr of frames in the text file(n=) not equal the number of jpg files?
    Probably 3:2 pulldown. Post Mediainfo or GSpot info about the source.
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    Originally Posted by abeer View Post
    i treid it and finally i get an output, but the numebr of frames in the text file(n=) not equal the number of jpg files?
    Are you getting twice the number of images that n: reports?

    I got this behaviour last week when I was using ffmpeg to export images - but I completely forgot about it.

    Specifying the framerate of your source video with the '-r' option should fix this. The position of '-r' is important - it should go at the end of the list of parameters:
    Code:
    ffmpeg -i src.m2v -vf showinfo -f image2 img%05d.png -r 25 2>list.txt
    If your source video is 29.97fps, use -r 30000/1001
    Code:
    ffmpeg -i src.m2v -vf showinfo -f image2 img%05d.png -r 30000/1001 2>list.txt
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  6. For files with 3:2 pulldown (or other patterns) ffmpeg produces a frame for every field in the pulldown. So a 23.976 fps MPG file with pulldown flags will produce 59.94 image per second. And yes, you can use the -r parameter to specify the frame rate, -r 24000/1001 for 23.976 fps sources.
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    still the same, my file is 32.31 sec, 25fps, the images count 1-920, but the frames in the text is 0-811

    Name:  Capture.JPG
Views: 683
Size:  14.4 KB
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  8. is it a transport stream ? ffmpeg can have problems with transport streams

    can you post a video sample
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  9. 38 fps is an impossible frame rate for an MPG file.
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  10. Member
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    i includes video.mpg in the attachment it is my test file
    Image Attached Files
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  11. Member
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    I'm testing ffmpeg/showinfo with .MTS files taken with my Canon HFS21. Although I'm getting the right number of images to match the showinfo 'n:' value, for some reason showinfo isn't listing I-frames for (only B, P frames).

    But it works fine for other files on my system.
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  12. Member
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    this is the informaation about the file i use
    Click image for larger version

Name:	Capture.JPG
Views:	155
Size:	35.9 KB
ID:	10584
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  13. Originally Posted by abeer View Post
    i includes video.mpg in the attachment it is my test file
    Use ffmbc instead of ffmpeg, it will produce 1-811 images on your sample, starting at 00001

    You can find some pre-built windows binaries here
    http://www.mediafire.com/?8xynxe10rxb88
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  14. Member
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    thank you very much, i will try to extract the type information from the text file by matlab and i hope to get them.
    thanx alt
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  15. Member
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    Dear all

    I have a same problem to find a way in order to extract I, P & B frames from a MPEG file.
    whould you please help me? How can I do that?
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