ffmpeg 寻求计算错误的字节范围？

Question

我在尝试从特定时间戳的电影文件中提取缩略图时遇到问题。 一般来说，我对此没有任何问题，但我遇到了一组电影文件，它们收到有关请求的字节范围的错误（416 Requested Range Not Satisfiable）。

奇怪的是，服务器在部分内容请求中正确返回了内容长度，但是当它请求电影文件时，它请求的长度超过了这个长度。

这有点超出我的想象，所以我不确定这里会发生什么。 任何见解都会很棒。

命令：

/usr/bin/ffmpeg -y -ss 1400 -i 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4' -qscale:v 2 -f image2 -vframes 1 -filter:v 'scale=192:108' -loglevel debug /data/www/storage/test.jpg 2>&1

错误：

[https @ 0x22e1e00] header='HTTP/1.1 416 Requested Range Not Satisfiable'
[https @ 0x22e1e00] http_code=416
[https @ 0x22e1e00] HTTP error 416 Requested Range Not Satisfiable

源文件大小：

1776706045 bytes

源内容持续时间：

2897.624271

部分内容请求：

[https @ 0x22e1e00] header='HTTP/1.1 206 Partial Content'
[https @ 0x22e1e00] http_code=206
[https @ 0x22e1e00] header='x-amz-id-2: 4J1pgHExIUA0GxIxSBmGJjrRqliHbsIjXeuGzVfTlaaoVXbyZI5FQNma8fGaifcovkXfxJev5yU='
[https @ 0x22e1e00] header='x-amz-request-id: 78B3BDBB0356EF40'
[https @ 0x22e1e00] header='Date: Wed, 16 Dec 2015 23:51:29 GMT'
[https @ 0x22e1e00] header='x-amz-meta-content-length: 2898'
[https @ 0x22e1e00] header='x-amz-meta-cb-modifiedtime: Tue, 15 Dec 2015 17:59:51 GMT'
[https @ 0x22e1e00] header='Last-Modified: Wed, 16 Dec 2015 23:44:59 GMT'
[https @ 0x22e1e00] header='ETag: "6341a8022630667a8070a83575e542e7-27"'
[https @ 0x22e1e00] header='Accept-Ranges: bytes'
[https @ 0x22e1e00] header='Content-Range: bytes 0-1776706044/1776706045'
[https @ 0x22e1e00] header='Content-Type: video/mp4'
[https @ 0x22e1e00] header='Content-Length: 1776706045'
[https @ 0x22e1e00] header='Server: AmazonS3'
[https @ 0x22e1e00] header='Connection: close'

FFmpeg 请求：

request: GET /my-bucket/mymoviefile.mp4 HTTP/1.1
User-Agent: Lavf/56.25.101
Accept: */*
Range: bytes=1781732960-
Connection: close
Host: s3-us-west-2.amazonaws.com
Icy-MetaData: 1

整个日志：

# /usr/bin/ffmpeg -y -ss 1400 -i 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4' -qscale:v 2 -f image2 -vframes 1 -filter:v 'scale=192:108' -loglevel debug /data/www/storage/test.jpg 2>&1
ffmpeg version 2.6.4 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (Debian 4.9.2-10)
  configuration: --prefix=/usr --extra-cflags='-g -O2 -fstack-protector-strong -Wformat -Werror=format-security ' --extra-ldflags='-Wl,-z,relro' --cc='ccache cc' --enable-shared --enable-libmp3lame --enable-gpl --enable-nonfree --enable-libvorbis --enable-pthreads --enable-libfaac --enable-libxvid --enable-postproc --enable-x11grab --enable-libgsm --enable-libtheora --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libspeex --enable-nonfree --disable-stripping --enable-libvpx --enable-libschroedinger --disable-encoder=libschroedinger --enable-version3 --enable-libopenjpeg --enable-librtmp --enable-avfilter --enable-libfreetype --enable-libvo-aacenc --disable-decoder=amrnb --enable-libvo-amrwbenc --enable-libaacplus --libdir=/usr/lib/x86_64-linux-gnu --disable-vda --enable-libbluray --enable-libcdio --enable-gnutls --enable-frei0r --enable-openssl --enable-libass --enable-libopus --enable-fontconfig --enable-libpulse --disable-mips32r2 --disable-mipsdspr1 --disable-mipsdspr2 --enable-libvidstab --enable-libzvbi --enable-avresample --disable-htmlpages --disable-podpages --enable-libutvideo --enable-libfdk-aac --enable-libx265 --enable-libiec61883 --enable-vaapi --enable-libdc1394 --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Splitting the commandline.
Reading option '-y' ... matched as option 'y' (overwrite output files) with argument '1'.
Reading option '-ss' ... matched as option 'ss' (set the start time offset) with argument '1400'.
Reading option '-i' ... matched as input file with argument 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4'.
Reading option '-qscale:v' ... matched as option 'qscale' (use fixed quality scale (VBR)) with argument '2'.
Reading option '-f' ... matched as option 'f' (force format) with argument 'image2'.
Reading option '-vframes' ... matched as option 'vframes' (set the number of video frames to output) with argument '1'.
Reading option '-filter:v' ... matched as option 'filter' (set stream filtergraph) with argument 'scale=192:108'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument 'debug'.
Reading option '/data/www/storage/test.jpg' ... matched as output file.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option y (overwrite output files) with argument 1.
Applying option loglevel (set logging level) with argument debug.
Successfully parsed a group of options.
Parsing a group of options: input file https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4.
Applying option ss (set the start time offset) with argument 1400.
Successfully parsed a group of options.
Opening an input file: https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4.
[https @ 0x22e1e00] request: GET /my-bucket/mymoviefile.mp4 HTTP/1.1
User-Agent: Lavf/56.25.101
Accept: */*
Range: bytes=0-
Connection: close
Host: s3-us-west-2.amazonaws.com
Icy-MetaData: 1


[https @ 0x22e1e00] header='HTTP/1.1 206 Partial Content'
[https @ 0x22e1e00] http_code=206
[https @ 0x22e1e00] header='x-amz-id-2: 4J1pgHExIUA0GxIxSBmGJjrRqliHbsIjXeuGzVfTlaaoVXbyZI5FQNma8fGaifcovkXfxJev5yU='
[https @ 0x22e1e00] header='x-amz-request-id: 78B3BDBB0356EF40'
[https @ 0x22e1e00] header='Date: Wed, 16 Dec 2015 23:51:29 GMT'
[https @ 0x22e1e00] header='x-amz-meta-content-length: 2898'
[https @ 0x22e1e00] header='x-amz-meta-cb-modifiedtime: Tue, 15 Dec 2015 17:59:51 GMT'
[https @ 0x22e1e00] header='Last-Modified: Wed, 16 Dec 2015 23:44:59 GMT'
[https @ 0x22e1e00] header='ETag: "6341a8022630667a8070a83575e542e7-27"'
[https @ 0x22e1e00] header='Accept-Ranges: bytes'
[https @ 0x22e1e00] header='Content-Range: bytes 0-1776706044/1776706045'
[https @ 0x22e1e00] header='Content-Type: video/mp4'
[https @ 0x22e1e00] header='Content-Length: 1776706045'
[https @ 0x22e1e00] header='Server: AmazonS3'
[https @ 0x22e1e00] header='Connection: close'
[https @ 0x22e1e00] header=''
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] Format mov,mp4,m4a,3gp,3g2,mj2 probed with size=2048 and score=100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] ISO: File Type Major Brand: mp42
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] Before avformat_find_stream_info() pos: 1647960 bytes read:1652200 seeks:0
[h264 @ 0x22e92c0] no picture
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] All info found
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] After avformat_find_stream_info() pos: 1862326 bytes read:1878504 seeks:0 frames:16
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 1
    compatible_brands: isommp41avc1
    creation_time   : 2015-11-18 02:34:41
  Duration: 00:48:17.70, start: 0.000000, bitrate: 4905 kb/s
    Stream #0:0(und), 15, 1/2997: Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, left), 1920x1080 (1920x1088) [SAR 1:1 DAR 16:9], 1001/60000, 9994 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 59.94 tbc (default)
    Metadata:
      creation_time   : 2015-11-18 02:34:41
      handler_name    : ?Apple Video Media Handler
    Stream #0:1(und), 1, 1/48000: Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
    Metadata:
      creation_time   : 2015-11-18 02:34:41
      handler_name    : ?Apple Sound Media Handler
Successfully opened the file.
Parsing a group of options: output file /data/www/storage/test.jpg.
Applying option qscale:v (use fixed quality scale (VBR)) with argument 2.
Applying option f (force format) with argument image2.
Applying option vframes (set the number of video frames to output) with argument 1.
Applying option filter:v (set stream filtergraph) with argument scale=192:108.
Successfully parsed a group of options.
Opening an output file: /data/www/storage/test.jpg.
Successfully opened the file.
detected 2 logical cores
[Parsed_scale_0 @ 0x22cd4c0] Setting 'w' to value '192'
[Parsed_scale_0 @ 0x22cd4c0] Setting 'h' to value '108'
[Parsed_scale_0 @ 0x22cd4c0] Setting 'flags' to value '0x4'
[Parsed_scale_0 @ 0x22cd4c0] w:192 h:108 flags:'0x4' interl:0
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'video_size' to value '1920x1080'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'pix_fmt' to value '0'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'time_base' to value '1/2997'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'pixel_aspect' to value '1/1'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'sws_param' to value 'flags=2'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'frame_rate' to value '2997/100'
[graph 0 input from stream 0:0 @ 0x22ccfe0] w:1920 h:1080 pixfmt:yuv420p tb:1/2997 fr:2997/100 sar:1/1 sws_param:flags=2
[format @ 0x2798640] compat: called with args=[yuvj420p|yuvj422p|yuvj444p]
[format @ 0x2798640] Setting 'pix_fmts' to value 'yuvj420p|yuvj422p|yuvj444p'
[AVFilterGraph @ 0x22cda60] query_formats: 5 queried, 4 merged, 0 already done, 0 delayed
[Parsed_scale_0 @ 0x22cd4c0] picking yuvj420p out of 3 ref:yuv420p alpha:0
[swscaler @ 0x22c3c80] deprecated pixel format used, make sure you did set range correctly
[Parsed_scale_0 @ 0x22cd4c0] w:1920 h:1080 fmt:yuv420p sar:1/1 -> w:192 h:108 fmt:yuvj420p sar:1/1 flags:0x4
[mjpeg @ 0x2854e20] intra_quant_bias = 96 inter_quant_bias = 0
[mjpeg @ 0x28716c0] intra_quant_bias = 96 inter_quant_bias = 0
[mjpeg @ 0x2795320] intra_quant_bias = 96 inter_quant_bias = 0
Output #0, image2, to '/data/www/storage/test.jpg':
  Metadata:
    major_brand     : mp42
    minor_version   : 1
    compatible_brands: isommp41avc1
    encoder         : Lavf56.25.101
    Stream #0:0(und), 0, 100/2997: Video: mjpeg, yuvj420p(pc, left), 192x108 [SAR 1:1 DAR 16:9], 100/2997, q=2-31, 200 kb/s, 29.97 fps, 29.97 tbn, 29.97 tbc (default)
    Metadata:
      creation_time   : 2015-11-18 02:34:41
      handler_name    : ?Apple Video Media Handler
      encoder         : Lavc56.26.100 mjpeg
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
Press [q] to stop, [?] for help
[https @ 0x22e1e00] request: GET /my-bucket/mymoviefile.mp4 HTTP/1.1
User-Agent: Lavf/56.25.101
Accept: */*
Range: bytes=1781732960-
Connection: close
Host: s3-us-west-2.amazonaws.com
Icy-MetaData: 1


[https @ 0x22e1e00] header='HTTP/1.1 416 Requested Range Not Satisfiable'
[https @ 0x22e1e00] http_code=416
[https @ 0x22e1e00] HTTP error 416 Requested Range Not Satisfiable
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] stream 0, offset 0x6a331660: partial file
https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4: Invalid data found when processing input
[output stream 0:0 @ 0x22d7500] EOF on sink link output stream 0:0:default.
No more output streams to write to, finishing.
frame=    0 fps=0.0 q=0.0 Lsize=N/A time=00:00:00.00 bitrate=N/A
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Input file #0 (https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4):
  Input stream #0:0 (video): 0 packets read (0 bytes); 0 frames decoded;
  Input stream #0:1 (audio): 0 packets read (0 bytes);
  Total: 0 packets (0 bytes) demuxed
Output file #0 (/data/www/storage/test.jpg):
  Output stream #0:0 (video): 0 frames encoded; 0 packets muxed (0 bytes);
  Total: 0 packets (0 bytes) muxed
Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
0 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0x27ab100] Statistics: 1878504 bytes read, 0 seeks

FFprobe 结果：

# /usr/bin/ffprobe -show_format -show_streams -i 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4'
ffprobe version 2.6.4 Copyright (c) 2007-2015 the FFmpeg developers
  built with gcc 4.9.2 (Debian 4.9.2-10)
  configuration: --prefix=/usr --extra-cflags='-g -O2 -fstack-protector-strong -Wformat -Werror=format-security ' --extra-ldflags='-Wl,-z,relro' --cc='ccache cc' --enable-shared --enable-libmp3lame --enable-gpl --enable-nonfree --enable-libvorbis --enable-pthreads --enable-libfaac --enable-libxvid --enable-postproc --enable-x11grab --enable-libgsm --enable-libtheora --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libspeex --enable-nonfree --disable-stripping --enable-libvpx --enable-libschroedinger --disable-encoder=libschroedinger --enable-version3 --enable-libopenjpeg --enable-librtmp --enable-avfilter --enable-libfreetype --enable-libvo-aacenc --disable-decoder=amrnb --enable-libvo-amrwbenc --enable-libaacplus --libdir=/usr/lib/x86_64-linux-gnu --disable-vda --enable-libbluray --enable-libcdio --enable-gnutls --enable-frei0r --enable-openssl --enable-libass --enable-libopus --enable-fontconfig --enable-libpulse --disable-mips32r2 --disable-mipsdspr1 --disable-mipsdspr2 --enable-libvidstab --enable-libzvbi --enable-avresample --disable-htmlpages --disable-podpages --enable-libutvideo --enable-libfdk-aac --enable-libx265 --enable-libiec61883 --enable-vaapi --enable-libdc1394 --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 1
    compatible_brands: isommp41avc1
    creation_time   : 2015-11-18 02:34:41
  Duration: 00:48:17.70, start: 0.000000, bitrate: 4905 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv), 1920x1080 [SAR 1:1 DAR 16:9], 9994 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 59.94 tbc (default)
    Metadata:
      creation_time   : 2015-11-18 02:34:41
      handler_name    : ?Apple Video Media Handler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
    Metadata:
      creation_time   : 2015-11-18 02:34:41
      handler_name    : ?Apple Sound Media Handler
[STREAM]
index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=High
codec_type=video
codec_time_base=1001/60000
codec_tag_string=avc1
codec_tag=0x31637661
width=1920
height=1080
has_b_frames=1
sample_aspect_ratio=1:1
display_aspect_ratio=16:9
pix_fmt=yuv420p
level=40
color_range=tv
color_space=unknown
color_transfer=unknown
color_primaries=unknown
chroma_location=left
timecode=N/A
refs=3
is_avc=1
nal_length_size=4
id=N/A
r_frame_rate=2997/100
avg_frame_rate=2997/100
time_base=1/2997
start_pts=0
start_time=0.000000
duration_ts=8684300
duration=2897.664331
bit_rate=9994429
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=86843
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
TAG:creation_time=2015-11-18 02:34:41
TAG:language=und
TAG:handler_name=Apple Video Media Handler
[/STREAM]
[STREAM]
index=1
codec_name=aac
codec_long_name=AAC (Advanced Audio Coding)
profile=LC
codec_type=audio
codec_time_base=1/48000
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=0.000000
duration_ts=139085965
duration=2897.624271
bit_rate=192002
max_bit_rate=N/A
bits_per_raw_sample=N/A
nb_frames=135828
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
TAG:creation_time=2015-11-18 02:34:41
TAG:language=und
TAG:handler_name=Apple Sound Media Handler
[/STREAM]
[FORMAT]
filename=https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4
nb_streams=2
nb_programs=0
format_name=mov,mp4,m4a,3gp,3g2,mj2
format_long_name=QuickTime / MOV
start_time=0.000000
duration=2897.695000
size=1776706045
bit_rate=4905156
probe_score=100
TAG:major_brand=mp42
TAG:minor_version=1
TAG:compatible_brands=isommp41avc1
TAG:creation_time=2015-11-18 02:34:41
[/FORMAT]

Answer 1

我遇到了同样的错误，我发现这个错误已在 ffmpeg 4.2 中修复。 尝试升级您的 ffmpeg，它应该可以正常工作。

https://github.com/FFmpeg/FFmpeg/commit/69fcc093c1241b5ee7711c56c9cd558832a7e491

Answer 2

我观察到了同样的 BUG，并在 ffmpeg 的源代码周围挖掘证实了这一点。 问题在于，ffmpeg 没有使用 Content-Length 作为文件大小，而是错误地使用了 Content-Range 中的最后一个值。

存在一种具有潜在性能影响的解决方法，只需添加-seekable 0