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  • FFMPEG : preset not found in Windows Vista

    18 mars, par StackOverflowNewbie

    I download FFMPEG from http://www.videohelp.com/tools/ffmpeg#download and saved it in my c:\program files\ffmpeg (Windows Vista). My Path's first 2 entries are:

    c:\program files\ffmpeg\bin;c:\program files\ffmpeg\presets;

    I found the following command on the net (http://paulrouget.com/e/converttohtml5video/)

    ffmpeg -i input.avi -acodec libvorbis -ab 96k -vcodec libx264 -vpre main -level 21 -refs 2 -b 345k -bt 345k -threads 0 -s 320x240 output.mp4

    When I run this on command line, I get the following error:

    File for preset main not found

    Any ideas what might be wrong?

  • Is it possible to embed ffplay ?

    18 mars, par EthanL

    ffmpeg's viewer, ffplay, has a lot of great options for optimizing viewing experience. I've been able to get it to nicely display an RTSP stream at low latency. However, it's been difficult to include it in a GUI.

    Is that possible? Is there a GUI that does that?

    Note: I am NOT trying to embed in a browser, or just toss the window on top of a GUI.

    Best solution: desktop GUI that includes ffplay in a widget

    First alternative: desktop GUI that has variable opacity. If the ffplay window is layered below the GUI, and the GUI is transparent, it could look decent. However, some buttons would have to be visible, so the entire window can't be transparent.

    Second alternative: disable the possibility of user interaction with the ffplay window. Then, the ffplay window could just be tossed to the side of the screen, and it would remain there as a split screen, without concern that a user could minimize it or move it.

  • How to have a clean transition when concat MTS files using ffmpeg ?

    18 mars, par pho

    I have been struggling for a while and I hope someone can help me. What I want to do: 1- seek MTS files 2- conact them without re-encoding them

    How I do that: I write a file concatList.txt

    file 'file1.MTS'
file 'file1_cut.MTS'

    I execute

    ffmpeg -y -i file1.MTS -ss 11.5 -c copy -copyts file1_cut.MTS
ffmpeg -y -f concat -i concatList.txt -c copy output.MTS

    (11.5s corresponds to an I-frame)

    The transition between the two videos in output.MTS is very buggy during more than 1s

    To dig in, I tried to analyse the streams but it rises many questions:

    ffprobe -select_streams v -show_entries frame=pict_type,pts_time,pic_type,pts -skip_frame nokey -of compact -i file1.MTS

    pts;pts_time;pict_type
147600;1.640000;I
100800;1.120000;I
1083600;12.040000;I
1036800;11.520000;I ==> I cut the file here
2019600;22.440000;I
1972800;21.920000;I
2955600;32.840000;I
2908800;32.320000;I

    ==> Why not all I-frames are found by the -skip_frame nokey option ?

    ffmpeg -y -i file1_cut.MTS -map v:0 -c copy -copyts -f framemd5 file1_cut.md5

    combined with the following command output

    ffprobe -select_streams v -show_entries frame=pict_type,pts_time,pic_type,pts -of compact -i file1_cut.MTS

    stream;dts;diff_dts;pts;duration;size;hash;pts_time;pict_type
0;163800;0;174600;1800;197323;7e228dfab2cb38922cab06844d67bf8c;1.94;I ==> This is the correct I-frame
0;165600;1800;176400;1800;28860;80ef4505813b99bb4484c969f589fa35;;
0;167400;1800;167400;1800;30289;d172722d01631a13caed81fc6be5b828;; ==> Why no frame type found by ffprobe ??
0;169200;1800;169200;1800;23338;e22eb396408abbf66bd6ef4f8893d102;;
0;171000;1800;171000;1800;24414;1a4f128017e8fc239b6c728f0c6d45b2;; ==> Why no frame type found by ffprobe ??
0;172800;1800;172800;1800;28872;acd07b2f3ccbddd072c380bee709a2dc;;
0;174600;1800;181800;1800;42872;eb225b253ebd427f2af01c2861d684c7;2.02;P
0;176400;1800;183600;1800;35942;58a238b781b1bfe720aa6de61830e3b1;;
0;178200;1800;178200;1800;22080;c6b43fbf1083d40499d908f0f02bd3dd;1.98;B
0;180000;1800;180000;1800;24896;4481d088ad425da908daa83220111fd2;;
0;181800;1800;189000;1800;40733;1294f59fe24d17aa8ca34fc327631d80;2.1;P
0;183600;1800;190800;1800;37904;095f7be43c90e97d66fb8427a17cb4c3;;
0;185400;1800;185400;1800;25808;a9d4e63c7607fcf9cd491084cce556ba;2.06;B
0;187200;1800;187200;1800;24874;834117a8d7e106a2278c412ec0acd1df;;

    ffmpeg -y -i output.MTS -map v:0 -c copy -copyts -f framemd5 output.md5

    combined with the following command output

    ffprobe -select_streams v -show_entries frame=pict_type,pts_time,pic_type,pts -of compact -i output.MTS

    stream;dts;diff_dts;pts;duration;size;hash;pts_time;pict_type
0;3106800;1800;3114000;1800;45853;7d5c2b6c9f4e1da8f93782b1de7de3a7;34.6;P;
0;3108600;1800;3115800;1800;43213;b07554ad625850e3a4b8de54be6af1dd;;;
0;3110400;1800;3110400;1800;25764;85c4aa6e62db831617a13bf5e6e08dda;34.56;B;
0;3112200;1800;3112200;1800;24328;2e6bac4090917f2bc6ccedc8841612c5;;;
0;3114000;1800;3121200;1800;46802;dfac0337af77c1a895e900048fc757c5;34.68;P; ==> Why pts larger than pts of first file1_cut.MTS frames ??
0;3115800;1800;3123000;1800;41795;b33af7f2e6ca04c3179ef52c37df4fe5;;;
0;3117600;1800;3117600;1800;23488;41a48cd53a2400d9331766ce3565c55c;34.64;B;
0;3119400;1800;3119400;1800;23222;cc85ec074b62a0c51ac8e4e1196db079;;; ==> Last frame of file1.MTS
0;3162240;42840;3173040;1800;197323;7e228dfab2cb38922cab06844d67bf8c;;; ==> First frame of file1_cut.MTS, ==> Why a lag of 42840 (0.4s) between two successive dts ??
0;3164040;1800;3174840;1800;28860;80ef4505813b99bb4484c969f589fa35;;;
0;3165840;1800;3165840;1800;30289;d172722d01631a13caed81fc6be5b828;;; ==> Why all these frames are not detected by ffprobe ??
0;3167640;1800;3167640;1800;23338;e22eb396408abbf66bd6ef4f8893d102;;;
0;3169440;1800;3169440;1800;24414;1a4f128017e8fc239b6c728f0c6d45b2;;;
0;3171240;1800;3171240;1800;28872;acd07b2f3ccbddd072c380bee709a2dc;;;
0;3173040;1800;3180240;1800;42872;eb225b253ebd427f2af01c2861d684c7;;;
0;3174840;1800;3182040;1800;35942;58a238b781b1bfe720aa6de61830e3b1;;;
0;3176640;1800;3176640;1800;22080;c6b43fbf1083d40499d908f0f02bd3dd;;;
0;3178440;1800;3178440;1800;24896;4481d088ad425da908daa83220111fd2;;;
0;3180240;1800;3187440;1800;40733;1294f59fe24d17aa8ca34fc327631d80;35.416;P;
0;3182040;1800;3189240;1800;37904;095f7be43c90e97d66fb8427a17cb4c3;;;
0;3183840;1800;3183840;1800;25808;a9d4e63c7607fcf9cd491084cce556ba;;; ==> Why ffprobe did not recognize the B-frame ??
0;3185640;1800;3185640;1800;24874;834117a8d7e106a2278c412ec0acd1df;;;
0;3187440;1800;3194640;1800;42645;13e6b4afb26734f0515303a5332dec32;35.496;P;
0;3189240;1800;3196440;1800;39393;cfd5bdc15737562fc40ac4527057a034;;;
0;3191040;1800;3191040;1800;25822;01b0d03c710f526c805c7aeaa54a39fb;35.456;B;
0;3192840;1800;3192840;1800;25089;8306d0ab9a0cbaf16283b2019337973e;;;
0;3194640;1800;3201840;1800;44593;1efb42bf015bbd71a54de2999ece272b;35.576;P;
0;3196440;1800;3203640;1800;40391;e6ff5568c1b019250ecd9d3568a7e7b5;;;
0;3198240;1800;3198240;1800;25354;c047b70a8a0725c4d60db8c92ea99706;35.536;B;

    So here is my main question: is there a "smart" concat command that cuts the frames of the first file that will never display (pts larger that the first frames of the second file), that anticipates the dts of I-frames of the second files, and that reduces the lag of dts to get a continuous stream?

    Thank you if anyone can answer.

  • Ffmpeg to duplicate an audio stream and encode this new stream

    18 mars, par sion

    I have some video files that I need to re-encode due to compatibility issues. They are currently mkv files with h.264 video and ac3-a52 audio. I want to keep the h.264 video, convert the container to m4v and create two audio tracks, one with the original ac3-a52 and one copied from that but in aac stereo.

    I assume there has to be some sort of audio stream mapping command but I don't know how to map and re-encode at the same time. What command should I enter into ffmpeg to achieve this?

    Also, what is the difference between ac3 and ac3-a52? Will an apple TV still be able to pass through ac3-a52 or does that have to be converted to ac3?

  • How to load file in ffmpeg in chunks ?

    18 mars, par developer1

    I'm having a problem when loading a larger file with ffmpeg in safari mobile, it crashes while doing that.

    Currently I'm loading the whole file at once await ffmpeg.writeFile(inputFileName, await fetchFile(file)); and to my understanding safari tries to load it in-memory in one go and fails.

    How can I work around this issue? Maybe split the file to chunks? Maybe streaming?

    Thank you.

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