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Submit bugs and patches
13 avril 2011Unfortunately a software is never perfect.
If you think you have found a bug, report it using our ticket system. Please to help us to fix it by providing the following information : the browser you are using, including the exact version as precise an explanation as possible of the problem if possible, the steps taken resulting in the problem a link to the site / page in question
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Participer à sa traduction
10 avril 2011Vous pouvez nous aider à améliorer les locutions utilisées dans le logiciel ou à traduire celui-ci dans n’importe qu’elle nouvelle langue permettant sa diffusion à de nouvelles communautés linguistiques.
Pour ce faire, on utilise l’interface de traduction de SPIP où l’ensemble des modules de langue de MediaSPIP sont à disposition. ll vous suffit de vous inscrire sur la liste de discussion des traducteurs pour demander plus d’informations.
Actuellement MediaSPIP n’est disponible qu’en français et (...) -
Installation en mode ferme
4 février 2011, parLe mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
C’est la méthode que nous utilisons sur cette même plateforme.
L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...)
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6 Crucial Benefits of Conversion Rate Optimisation
26 février 2024, par Erin -
When I use ffmpeg to go from a video to frames, and then back to video, the duration is different between the videos
24 février 2024, par bluepandaI am trying to use
ffmpeg
to convert from a .mp4 (or .mov) video into individual frames, do some processing on those frames, and then convert back to .mp4. The problem is that the resulting video I create is a different duration than the input - I can see this visually when I play the two videos side by side. The difference is not large (i.e.00:00:00.50
for the input video and00:00:00.52
for the output video), but when the videos are looped next to each other they get out of sync.

Here is information about the input video retrieved using
fluent-ffmpeg
'sffmpeg.ffprobe(videoPath)
:

metadata {
 streams: [
 {
 index: 0,
 codec_name: 'h264',
 codec_long_name: 'H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10',
 profile: 'High',
 codec_type: 'video',
 codec_tag_string: 'avc1',
 codec_tag: '0x31637661',
 width: 1080,
 height: 1920,
 coded_width: 1080,
 coded_height: 1920,
 closed_captions: 0,
 has_b_frames: 2,
 sample_aspect_ratio: 'N/A',
 display_aspect_ratio: 'N/A',
 pix_fmt: 'yuv420p',
 level: 40,
 color_range: 'tv',
 color_space: 'bt709',
 color_transfer: 'bt709',
 color_primaries: 'bt709',
 chroma_location: 'left',
 field_order: 'unknown',
 refs: 1,
 is_avc: 'true',
 nal_length_size: 4,
 id: 'N/A',
 r_frame_rate: '30000/1001',
 avg_frame_rate: '27000/1001',
 time_base: '1/30000',
 start_pts: 0,
 start_time: 0,
 duration_ts: 15100,
 duration: 0.503333,
 bit_rate: 5660223,
 max_bit_rate: 'N/A',
 bits_per_raw_sample: 8,
 nb_frames: 36,
 nb_read_frames: 'N/A',
 nb_read_packets: 'N/A',
 tags: [Object],
 disposition: [Object]
 },
 {
 index: 1,
 codec_name: 'aac',
 codec_long_name: 'AAC (Advanced Audio Coding)',
 profile: 'LC',
 codec_type: 'audio',
 codec_tag_string: 'mp4a',
 codec_tag: '0x6134706d',
 sample_fmt: 'fltp',
 sample_rate: 48000,
 channels: 2,
 channel_layout: 'stereo',
 bits_per_sample: 0,
 id: 'N/A',
 r_frame_rate: '0/0',
 avg_frame_rate: '0/0',
 time_base: '1/48000',
 start_pts: 0,
 start_time: 0,
 duration_ts: 24160,
 duration: 0.503333,
 bit_rate: 248416,
 max_bit_rate: 'N/A',
 bits_per_raw_sample: 'N/A',
 nb_frames: 27,
 nb_read_frames: 'N/A',
 nb_read_packets: 'N/A',
 tags: [Object],
 disposition: [Object]
 }
 ],
 format: {
 filename: '/Users/name/images/input.mp4',
 nb_streams: 2,
 nb_programs: 0,
 format_name: 'mov,mp4,m4a,3gp,3g2,mj2',
 format_long_name: 'QuickTime / MOV',
 start_time: 0,
 duration: 0.503333,
 size: 963879,
 bit_rate: 15319941,
 probe_score: 100,
 tags: {
 major_brand: 'mp42',
 minor_version: '1',
 compatible_brands: 'isommp41mp42',
 creation_time: '2024-02-14T01:21:12.000000Z'
 }
 },
 chapters: []
}



and here is from running
ffprobe
directly :

ffprobe '/Users/name/images/input.mp4'
ffprobe version 6.1.1 Copyright (c) 2007-2023 the FFmpeg developers
 built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)
 configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/6.1.1_2 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopenvino --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox --enable-audiotoolbox --enable-neon
 libavutil 58. 29.100 / 58. 29.100
 libavcodec 60. 31.102 / 60. 31.102
 libavformat 60. 16.100 / 60. 16.100
 libavdevice 60. 3.100 / 60. 3.100
 libavfilter 9. 12.100 / 9. 12.100
 libswscale 7. 5.100 / 7. 5.100
 libswresample 4. 12.100 / 4. 12.100
 libpostproc 57. 3.100 / 57. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/name/images/input.mp4':
 Metadata:
 major_brand : mp42
 minor_version : 1
 compatible_brands: isommp41mp42
 creation_time : 2024-02-14T01:21:12.000000Z
 Duration: 00:00:00.50, start: 0.000000, bitrate: 15319 kb/s
 Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709, progressive), 1080x1920, 5660 kb/s, 26.97 fps, 29.97 tbr, 30k tbn (default)
 Metadata:
 creation_time : 2024-02-14T01:21:12.000000Z
 handler_name : Core Media Video
 vendor_id : [0][0][0][0]
 encoder : AVC Coding
 Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 248 kb/s (default)
 Metadata:
 creation_time : 2024-02-14T01:21:12.000000Z
 handler_name : Core Media Audio
 vendor_id : [0][0][0][0]



And this is my command to go from video to frames :


ffmpeg -i /Users/name/images/input.mp4 -y -f image2 /Users/name/images/frames/%d.png



After which I convert the frames back to video with this - note that I get by seeing
avg_frame_rate
is27000/1001 = 26.97302697
:

ffmpeg -r 26.973026973026972 -i /Users/name/images/frames/%d.png -y -r 26.973026973026972 -b:v 5660223k -f mp4 -pix_fmt yuv420p -t 0.503333 /Users/name/images/output.mp4



And if I then run
fluent-ffmpeg
'sffmpeg.ffprobe(videoPath)
I get :

metadata {
 streams: [
 {
 index: 0,
 codec_name: 'h264',
 codec_long_name: 'H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10',
 profile: 'High',
 codec_type: 'video',
 codec_tag_string: 'avc1',
 codec_tag: '0x31637661',
 width: 1080,
 height: 1920,
 coded_width: 1080,
 coded_height: 1920,
 closed_captions: 0,
 has_b_frames: 2,
 sample_aspect_ratio: '1:1',
 display_aspect_ratio: '9:16',
 pix_fmt: 'yuv420p',
 level: 62,
 color_range: 'unknown',
 color_space: 'unknown',
 color_transfer: 'unknown',
 color_primaries: 'unknown',
 chroma_location: 'left',
 field_order: 'unknown',
 refs: 1,
 is_avc: 'true',
 nal_length_size: 4,
 id: 'N/A',
 r_frame_rate: '27000/1001',
 avg_frame_rate: '27000/1001',
 time_base: '1/27000',
 start_pts: 0,
 start_time: 0,
 duration_ts: 14014,
 duration: 0.519037,
 bit_rate: 52138429,
 max_bit_rate: 'N/A',
 bits_per_raw_sample: 8,
 nb_frames: 14,
 nb_read_frames: 'N/A',
 nb_read_packets: 'N/A',
 tags: [Object],
 disposition: [Object]
 }
 ],
 format: {
 filename: '/Users/name/images/output.mp4',
 nb_streams: 1,
 nb_programs: 0,
 format_name: 'mov,mp4,m4a,3gp,3g2,mj2',
 format_long_name: 'QuickTime / MOV',
 start_time: 0,
 duration: 0.52,
 size: 3383708,
 bit_rate: 52057046,
 probe_score: 100,
 tags: {
 major_brand: 'isom',
 minor_version: '512',
 compatible_brands: 'isomiso2avc1mp41',
 encoder: 'Lavf60.3.100'
 }
 },
 chapters: []
}



and here is from running
ffprobe
directly :

ffprobe '/Users/name/images/output.mp4'
ffprobe version 6.1.1 Copyright (c) 2007-2023 the FFmpeg developers
 built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)
 configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/6.1.1_2 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopenvino --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox --enable-audiotoolbox --enable-neon
 libavutil 58. 29.100 / 58. 29.100
 libavcodec 60. 31.102 / 60. 31.102
 libavformat 60. 16.100 / 60. 16.100
 libavdevice 60. 3.100 / 60. 3.100
 libavfilter 9. 12.100 / 9. 12.100
 libswscale 7. 5.100 / 7. 5.100
 libswresample 4. 12.100 / 4. 12.100
 libpostproc 57. 3.100 / 57. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/name/images/output.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 encoder : Lavf60.3.100
 Duration: 00:00:00.52, start: 0.000000, bitrate: 52153 kb/s
 Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 1080x1920 [SAR 1:1 DAR 9:16], 52138 kb/s, 26.97 fps, 26.97 tbr, 27k tbn (default)
 Metadata:
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
 encoder : Lavc60.3.100 libx264



This seems like it should be a fairly common scenario, but I have not been able to find examples of this, and the other questions about incorrect durations on Stack Overflow are about bigger differences (i.e. 3 seconds instead of 10 seconds : Wrong video duration when recording with ffmpeg).


Some other details :


- 

- I am running this through a Node.js script with
fluent-ffmpeg
, but I have also tried running the commands directly in the terminal and the result is the same. - I am fine with the output frames being .png / .jpg / other formats.
- I am fine with setting this to a different frame rate than the original as long as the two output videos end up with the same duration.
- One suspicious thing is that I set
-t 0.503333
when creating the video, but it doesn't seem to work as the result video showsduration: 0.519037
/00:00:00.52
.










Thank you for any help !


- I am running this through a Node.js script with
-
Attribution Tracking (What It Is and How It Works)
23 février 2024, par Erin