我正在尝试将 AVI 文件转换为 MP4 文件。视频流是 XVID，而音频流是 MP3。
问题是生成的 MP4 文件无法在 Mac 上的 QuickTime Player 中播放。它只能在 VLC 上播放。虽然这不是什么大问题，但我想知道如何解决此类问题。
该命令及其输出如下：
$ ffmpeg -i 103.avi -codec copy -f mp4 103.mp4
ffmpeg version N-60163-g78a9f18 Copyright (c) 2000-2014 the FFmpeg developers
built on Jan 25 2014 14:03:47 with Apple LLVM version 5.0 (clang-500.2.79) (based on LLVM 3.3svn)
configuration:
libavutil 52. 63.100 / 52. 63.100
libavcodec 55. 49.100 / 55. 49.100
libavformat 55. 26.100 / 55. 26.100
libavdevice 55. 5.102 / 55. 5.102
libavfilter 4. 1.101 / 4. 1.101
libswscale 2. 5.101 / 2. 5.101
libswresample 0. 17.104 / 0. 17.104
Input #0, avi, from '103.avi':
Metadata:
encoder : Lavf55.26.100
Duration: 00:49:36.43, start: 0.000000, bitrate: 986 kb/s
Stream #0:0: Video: mpeg4 (Advanced Simple Profile) (XVID / 0x44495658), yuv420p, 512x368 [SAR 1:1 DAR 32:23], 23.98 tbr, 23.98 tbn, 23.98 tbc
Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 48000 Hz, stereo, s16p, 121 kb/s
Output #0, mp4, to '103.mp4':
Metadata:
encoder : Lavf55.26.100
Stream #0:0: Video: mpeg4 ( [0][0][0] / 0x0020), yuv420p, 512x368 [SAR 1:1 DAR 32:23], q=2-31, 11988 tbn, 23.98 tbc
Stream #0:1: Audio: mp3 (i[0][0][0] / 0x0069), 48000 Hz, stereo, 121 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[mp4 @ 0x7fe5ca01fa00] pts has no value
Last message repeated 1555 times
[mp4 @ 0x7fe5ca01fa00] pts has no value9kB time=00:01:17.70 bitrate=1458.0kbits/s
Last message repeated 1041 times
[mp4 @ 0x7fe5ca01fa00] pts has no value49kB time=00:02:08.42 bitrate=1661.6kbits/s
Last message repeated 1906 times
[mp4 @ 0x7fe5ca01fa00] pts has no value53kB time=00:03:40.39 bitrate=1537.1kbits/s
Last message repeated 2136 times
[mp4 @ 0x7fe5ca01fa00] pts has no value93kB time=00:05:35.80 bitrate=1307.4kbits/s
Last message repeated 3519 times
[mp4 @ 0x7fe5ca01fa00] pts has no value32kB time=00:08:32.18 bitrate=1150.5kbits/s
Last message repeated 2813 times
[mp4 @ 0x7fe5ca01fa00] pts has no value88kB time=00:11:18.01 bitrate=1090.9kbits/s
Last message repeated 3057 times
[mp4 @ 0x7fe5ca01fa00] pts has no value39kB time=00:14:00.42 bitrate=1028.7kbits/s
Last message repeated 3731 times
[mp4 @ 0x7fe5ca01fa00] pts has no value11kB time=00:16:57.72 bitrate= 991.0kbits/s
Last message repeated 2658 times
[mp4 @ 0x7fe5ca01fa00] pts has no value76kB time=00:19:25.70 bitrate= 978.1kbits/s
Last message repeated 2167 times
[mp4 @ 0x7fe5ca01fa00] pts has no value70kB time=00:21:17.11 bitrate= 990.8kbits/s
Last message repeated 3663 times
[mp4 @ 0x7fe5ca01fa00] pts has no value20kB time=00:24:42.06 bitrate= 938.1kbits/s
Last message repeated 2335 times
[mp4 @ 0x7fe5ca01fa00] pts has no value79kB time=00:26:53.90 bitrate= 950.6kbits/s
Last message repeated 4153 times
[mp4 @ 0x7fe5ca01fa00] pts has no value06kB time=00:30:59.94 bitrate= 895.4kbits/s
Last message repeated 3168 times
[mp4 @ 0x7fe5ca01fa00] pts has no value87kB time=00:33:35.43 bitrate= 888.5kbits/s
Last message repeated 1565 times
[mp4 @ 0x7fe5ca01fa00] pts has no value02kB time=00:34:56.47 bitrate= 914.0kbits/s
Last message repeated 2792 times
[mp4 @ 0x7fe5ca01fa00] pts has no value10kB time=00:37:34.42 bitrate= 909.6kbits/s
Last message repeated 2503 times
[mp4 @ 0x7fe5ca01fa00] pts has no value49kB time=00:39:48.76 bitrate= 916.2kbits/s
Last message repeated 1714 times
[mp4 @ 0x7fe5ca01fa00] pts has no value70kB time=00:41:16.64 bitrate= 928.7kbits/s
Last message repeated 2060 times
[mp4 @ 0x7fe5ca01fa00] pts has no value79kB time=00:43:04.79 bitrate= 935.2kbits/s
Last message repeated 1349 times
[mp4 @ 0x7fe5ca01fa00] pts has no value46kB time=00:44:06.57 bitrate= 951.6kbits/s
Last message repeated 2354 times
[mp4 @ 0x7fe5ca01fa00] pts has no value67kB time=00:45:56.33 bitrate= 967.9kbits/s
Last message repeated 2668 times
[mp4 @ 0x7fe5ca01fa00] pts has no value50kB time=00:48:14.72 bitrate= 964.9kbits/s
Last message repeated 1655 times
frame=71363 fps=5738 q=-1.0 Lsize= 355528kB time=00:49:36.43 bitrate= 978.5kbits/s
video:309630kB audio:44196kB subtitle:0 global headers:0kB muxing overhead 0.481011%
如果我再次复制 mp4，我会得到以下结果：
$ ffmpeg -i 103.mp4 -codec copy -f mp4 103-new.mp4
ffmpeg version N-60163-g78a9f18 Copyright (c) 2000-2014 the FFmpeg developers
built on Jan 25 2014 14:03:47 with Apple LLVM version 5.0 (clang-500.2.79) (based on LLVM 3.3svn)
configuration:
libavutil 52. 63.100 / 52. 63.100
libavcodec 55. 49.100 / 55. 49.100
libavformat 55. 26.100 / 55. 26.100
libavdevice 55. 5.102 / 55. 5.102
libavfilter 4. 1.101 / 4. 1.101
libswscale 2. 5.101 / 2. 5.101
libswresample 0. 17.104 / 0. 17.104
[mpeg4 @ 0x7fcddb018000] Video uses a non-standard and wasteful way to store B-frames ('packed B-frames'). Consider using a tool like VirtualDub or avidemux to fix it.
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '103.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2mp41
encoder : Lavf55.26.100
Duration: 00:49:36.44, start: 0.000000, bitrate: 978 kb/s
Stream #0:0(und): Video: mpeg4 (Advanced Simple Profile) (mp4v / 0x7634706D), yuv420p, 512x368 [SAR 1:1 DAR 32:23], 852 kb/s, 23.98 fps, 23.98 tbr, 11988 tbn, 23.98 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(und): Audio: mp3 (mp4a / 0x6134706D), 48000 Hz, stereo, s16p, 121 kb/s (default)
Metadata:
handler_name : SoundHandler
Output #0, mp4, to '103-new.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2mp41
encoder : Lavf55.26.100
Stream #0:0(und): Video: mpeg4 ( [0][0][0] / 0x0020), yuv420p, 512x368 [SAR 1:1 DAR 32:23], q=2-31, 852 kb/s, 23.98 fps, 11988 tbn, 11988 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(und): Audio: mp3 (i[0][0][0] / 0x0069), 48000 Hz, stereo, 121 kb/s (default)
Metadata:
handler_name : SoundHandler
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=71363 fps=5505 q=-1.0 Lsize= 355528kB time=00:49:36.43 bitrate= 978.5kbits/s
video:309567kB audio:44196kB subtitle:0 global headers:0kB muxing overhead 0.498835%
答案1
首先，介绍一下此错误出现的原因。AVI 不支持可变帧速率视频。因此，在文件开头的某个地方会记录帧速率。mp4 支持可变帧速率，因此需要知道每帧的持续时间。在 ffmpeg 中，固定帧速率视频的 pts 生成通常由解码器处理。但通过使用-codec copy，您可以绕过解码器。
解决方案正在指定-fflags +genpts（必须在使用 指定输入文件之前-i）。
答案2
我发现对帧速率进行硬编码可以解决这个问题：
ffmpeg -r 25 -i test.h264 -codec copy testout25.mp4
（我仍然收到警告“流 0 中的数据包中的时间戳未设置”，但生成的文件可以在 Mac 上的 Quicktime Player 中查找。）
答案3
放在& 之前-ss 0.000000，意味着你将有两个。-i-c:v-ss 0.000000
-probesize=(VideoSizeInBytes x 10)仅在第一个之前添加-ss 0.000000。Probesize 的计算方式如下：-probesize=3865000000对于386Mb文件 ( 386500000x 10)。
-vsync 0不得用于此目的。不再pts has no value存在问题。