Questions about fps and synch for vintage QuickTime movies
I am retiring some old computer equipment, and want to transcode some old QuickTime movies into a modern format. These movies were found on removable media with dates in the spring of 1996. I think they were made on my PowerMac 7500/100, on those dates or not many years before. That would be with System 7.5.something. I think I made them using some standard recording software of such Macs. I think the video source was a S-VHS camcorder, connected to the Mac via a S-video cable; the audio came in through the Mac's microphone or an external microphone. In Mac filesystem terms, these movies have type/creator of MooV/ttxt. Each has a small resource fork, containing just one resource (of type MooV), and a large data fork. I have copied these files to modern systems, losing the resource fork along the way. I can play them with mplayer and QuickTime 7 on Windows Vista and MacOS 10.6 (also the current QuickTime on MacOS 10). Oddly, mplayer and QuickTime disagree about the frame rate. I will discuss one example movie. On both MacOS 10 and Windows Vista, QuickTime 7's inspector says the movie's frame rate is 27.16. On both MacOS 10 and Windows Vista, mplayer says the movie's frame rate is 30.00. In all four cases, when I play the move the sound and video are in sync. I used a stopwatch to time the playback time between two events in the movie (it is short), and got the same amount (33 seconds) in each of those four cases. Why are these two pieces of software making different claims about FPS? When I try to transcode, using mencode, the sound and video get out of sync. I am guessing that understanding what is going on with the source will help. Thanks, Mike
Mike Spreitzer <mspreitz <at> us.ibm.com> writes:
I used a stopwatch to time the playback time between two events in the movie (it is short), and got the same amount (33 seconds) in each of those four cases.
(FFmpeg will tell you the number of frames, so you will easily find out the actual fps, but see below.)
Why are these two pieces of software making different claims about FPS?
When I try to transcode, using mencode, the sound and video get out of sync.
Did you test ffmpeg -i input -qscale 2 out.avi ? If that also produces out-of-sync files, please provide a sample. I believe it is unlikely that the problem you see is in any way related to fps. Please do not cross-post, it is considered very rude, Carl Eugen
OK, ffmpeg is great. I can transcode with it, and it does not lose sync. However, I am a bit puzzled by one complaint. I tried exactly the command you suggested, and it complained that the original video frame rate is 600 per second! Here is a typescript: $ ffmpeg -i Problem1.mov -qscale 2 out.avi ffmpeg version 0.7.8, Copyright (c) 2000-2011 the FFmpeg developers built on Feb 20 2012 19:25:22 with gcc 4.2.1 (Apple Inc. build 5666) (dot 3) configuration: --prefix=/opt/local --enable-gpl --enable-postproc --enable-swscale --enable-avfilter --enable-libmp3lame --enable-libvorbis --enable-libtheora --enable-libdirac --enable-libschroedinger --enable-libopenjpeg --enable-libxvid --enable-libx264 --enable-libvpx --enable-libspeex --mandir=/opt/local/share/man --enable-shared --enable-pthreads --cc=/usr/bin/gcc-4.2 --arch=x86_64 --enable-yasm libavutil 50. 43. 0 / 50. 43. 0 libavcodec 52.123. 0 / 52.123. 0 libavformat 52.111. 0 / 52.111. 0 libavdevice 52. 5. 0 / 52. 5. 0 libavfilter 1. 80. 0 / 1. 80. 0 libswscale 0. 14. 1 / 0. 14. 1 libpostproc 51. 2. 0 / 51. 2. 0 Seems stream 0 codec frame rate differs from container frame rate: 600.00 (600/1) -> 30.00 (30/1) Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Problem1.mov': Metadata: major_brand : qt minor_version : 537199360 compatible_brands: qt creation_time : 2012-02-23 07:18:23 Duration: 00:00:31.08, start: 0.000000, bitrate: 9615 kb/s Stream #0.0(eng): Video: rawvideo, yuyv422, 160x120, 8203 kb/s, 26.71 fps, 30 tbr, 600 tbn, 600 tbc Metadata: creation_time : 2012-02-23 07:18:23 Stream #0.1(eng): Audio: pcm_s16be, 44100 Hz, 2 channels, s16, 1411 kb/s Metadata: creation_time : 2012-02-23 07:18:23 Incompatible pixel format 'yuyv422' for codec 'mpeg4', auto-selecting format 'yuv420p' [buffer @ 0x101b39f40] w:160 h:120 pixfmt:yuyv422 tb:1/1000000 sar:0/1 sws_param: [buffersink @ 0x101b3a180] auto-inserting filter 'auto-inserted scaler 0' between the filter 'src' and the filter 'out' [scale @ 0x101b3a400] w:160 h:120 fmt:yuyv422 -> w:160 h:120 fmt:yuv420p flags:0x4 Output #0, avi, to 'out.avi': Metadata: major_brand : qt minor_version : 537199360 compatible_brands: qt creation_time : 2012-02-23 07:18:23 ISFT : Lavf52.111.0 Stream #0.0(eng): Video: mpeg4, yuv420p, 160x120, q=2-31, 200 kb/s, 30 tbn, 30 tbc Metadata: creation_time : 2012-02-23 07:18:23 Stream #0.1(eng): Audio: mp2, 44100 Hz, 2 channels, s16, 64 kb/s Metadata: creation_time : 2012-02-23 07:18:23 Stream mapping: Stream #0.0 -> #0.0 Stream #0.1 -> #0.1 Press [q] to stop, [?] for help frame= 830 fps= 0 q=2.0 Lsize= 4631kB time=00:00:29.90 bitrate=1268.8kbits/s video:4328kB audio:243kB global headers:0kB muxing overhead 1.315741% $ I have not got permission from the (deceased) subjects of these movies to post them publicly, and can not produce new test movies in the same way because the equipment I originally used has decayed. BTW, I remembered that there was a step I omitted from my original description. What actually happened is I took images of the old mac disks (created, I think, in System 7.5.something) and mounted them in my newer MacOS 10.6 machine. This makes the resource fork visible to mac-savvy programs, such as Apple's QuickTime Player. I used the current QuickTime Player to open the old movie file, and to save it to a new file. It is the files save from QuickTime Player that I have been trying to transcode to other formats. The file Problem1.mov mentioned above is an example of a file saved by the current QuickTime Player. Thanks, Mike From: Carl Eugen Hoyos <cehoyos@ag.or.at> To: mencoder-users@mplayerhq.hu Date: 02/28/2012 07:38 AM Subject: Re: [MEncoder-users] Questions about fps and synch for vintage QuickTime movies Sent by: mencoder-users-bounces@mplayerhq.hu Mike Spreitzer <mspreitz <at> us.ibm.com> writes:
I used a stopwatch to time the playback time between two events in the movie (it is short), and got the same amount (33 seconds) in each of those four cases.
(FFmpeg will tell you the number of frames, so you will easily find out the actual fps, but see below.)
Why are these two pieces of software making different claims about FPS?
When I try to transcode, using mencode, the sound and video get out of sync.
Did you test ffmpeg -i input -qscale 2 out.avi ? If that also produces out-of-sync files, please provide a sample. I believe it is unlikely that the problem you see is in any way related to fps. Please do not cross-post, it is considered very rude, Carl Eugen _______________________________________________
On 2/26/12 5:29 PM, "Mike Spreitzer" <mspreitz@us.ibm.com> wrote:
I am retiring some old computer equipment, and want to transcode some old QuickTime movies into a modern format. These movies were found on removable media with dates in the spring of 1996. I think they were made on my PowerMac 7500/100, on those dates or not many years before. That would be with System 7.5.something. I think I made them using some standard recording software of such Macs. I think the video source was a S-VHS camcorder, connected to the Mac via a S-video cable; the audio came in through the Mac's microphone or an external microphone. In Mac filesystem terms, these movies have type/creator of MooV/ttxt. Each has a small resource fork, containing just one resource (of type MooV), and a large data fork.
I have copied these files to modern systems, losing the resource fork along the way. I can play them with mplayer and QuickTime 7 on Windows Vista and MacOS 10.6 (also the current QuickTime on MacOS 10). Oddly, mplayer and QuickTime disagree about the frame rate. I will discuss one example movie. On both MacOS 10 and Windows Vista, QuickTime 7's inspector says the movie's frame rate is 27.16. On both MacOS 10 and Windows Vista, mplayer says the movie's frame rate is 30.00. In all four cases, when I play the move the sound and video are in sync. I used a stopwatch to time the playback time between two events in the movie (it is short), and got the same amount (33 seconds) in each of those four cases. Why are these two pieces of software making different claims about FPS?
When I try to transcode, using mencode, the sound and video get out of sync. I am guessing that understanding what is going on with the source will help.
QuickTime generally displays average, not designated frame rate. I don't thing your sync problem is related to frame rate, either. Can you upload a sample? Then we could try some stuff on it and give you some command suggestions to try. Let us know what format you'd like for output, giving us a couple of options, if that's acceptable. Laine Lee
participants (3)
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Carl Eugen Hoyos -
L. Lee -
Mike Spreitzer