video - 使用 ffmpeg 转码为 DNxHD mxf 时，渐进式或隔行式被误解

Question

嗨，不知道是我做错了还是有错误。

尝试将带有立体声音频的 Quicktime Animation 隔行扫描上场的 1080i 视频转码为 MXF、DNxHD 以及谨慎的单声道音频 channel 和隔行扫描视频。
DNxHD = VC-3 op1a 120M。

除了最终结果被标记为渐进式之外，一切都像魅力一样!我可以看到，当我看视频时，它是交错的，很好看，所以一切都井井有条。

但是 MXF 文件将其自身识别为渐进式视频，因此我们的 Assets 管理系统将其视为 1080p 渐进式文件，Avid Mediacomposer 也是如此。

我无法解决 ffprobe 的问题，但我可以在 MediaInfo v0.7.69
下面 Selenium 。

我运行的命令:

./ffmpeg -i OLLETEST_MANSZELM_ANIMATION.mov -timecode 10:00:00:00 -threads 16 -map 0:0 -map 0:1 -map 0:1 -map_channel 0.1.0:0.1 -map_channel 0.1.1:0.2 -vcodec dnxhd -b:v 120M -acodec pcm_s24le -ar 48000 -flags +ildct -y test.mxf

使用媒体信息运行的转码文件报告了这个奇怪的结果。

Scan type                                : Progressive
Original scan type                       : Interlaced
Original scan order                      : Top Field First

似乎是 -flags +ildct不影响扫描类型:

ffmpeg 的输出:

Olles-MacBook-Pro-2:NoBackUp olso$ ./ffmpeg -i OLLETEST_MANSZELM_ANIMATION.mov -timecode 00:10:00:00 -threads 16 -map 0:0 -map 0:1 -map 0:1 -map_channel 0.1.0:0.1 -map_channel 0.1.1:0.2 -vcodec dnxhd -b:v 120M -acodec pcm_s24le -ar 48000  -flags +ildct -y test.mxf
ffmpeg version 2.6.2-tessus Copyright (c) 2000-2015 the FFmpeg developers
  built with Apple LLVM version 6.0 (clang-600.0.57) (based on LLVM 3.5svn)
  configuration: --cc=/usr/bin/clang --prefix=/Users/helmutt/data/ext/ffmpeg/sw --as=yasm --extra-version=tessus --disable-shared --enable-static --disable-ffplay --enable-gpl --enable-pthreads --enable-postproc --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libx265 --enable-libxvid --enable-libspeex --enable-bzlib --enable-zlib --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libxavs --enable-libsoxr --enable-libwavpack --enable-version3 --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvpx --enable-libgsm --enable-libopus --enable-libmodplug --enable-fontconfig --enable-libfreetype --enable-libass --enable-libbluray --enable-filters --disable-indev=qtkit --disable-indev=x11grab_xcb --enable-runtime-cpudetect
  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
  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 'OLLETEST_MANSZELM_ANIMATION.mov':
  Metadata:
    major_brand     : qt  
    minor_version   : 537199360
    compatible_brands: qt  
    creation_time   : 2015-04-14 20:40:41
  Duration: 00:00:11.04, start: 0.000000, bitrate: 1141927 kb/s
    Stream #0:0(eng): Video: qtrle (rle  / 0x20656C72), rgb24, 1920x1080, 1140363 kb/s, SAR 1:1 DAR 16:9, 25 fps, 25 tbr, 25 tbn, 25 tbc (default)
    Metadata:
      creation_time   : 2015-04-14 20:40:41
      handler_name    : Apple Alias Data Handler
      encoder         : Animation
      timecode        : 00:00:00:00
    Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, stereo, s16, 1536 kb/s (default)
    Metadata:
      creation_time   : 2015-04-14 20:40:41
      handler_name    : Apple Alias Data Handler
      timecode        : 00:00:00:00
    Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s (default)
    Metadata:
      creation_time   : 2015-04-14 20:41:01
      handler_name    : Apple Alias Data Handler
      timecode        : 00:00:00:00
-map_channel is forwarded to lavfi similarly to -af pan=0x4:c0=c0.
[pan @ 0x7f9db1e02600] This syntax is deprecated. Use '|' to separate the list items.
[pan @ 0x7f9db1e02600] Pure channel mapping detected: 0
-map_channel is forwarded to lavfi similarly to -af pan=0x4:c0=c1.
[pan @ 0x7f9db1d241e0] This syntax is deprecated. Use '|' to separate the list items.
[pan @ 0x7f9db1d241e0] Pure channel mapping detected: 1
Output #0, mxf, to 'test.mxf':
  Metadata:
    major_brand     : qt  
    minor_version   : 537199360
    compatible_brands: qt  
    timecode        : 00:10:00:00
    encoder         : Lavf56.25.101
    Stream #0:0(eng): Video: dnxhd, yuv422p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-1024, 120000 kb/s, 25 fps, 25 tbn, 25 tbc (default)
    Metadata:
      creation_time   : 2015-04-14 20:40:41
      handler_name    : Apple Alias Data Handler
      timecode        : 00:00:00:00
      encoder         : Lavc56.26.100 dnxhd
    Stream #0:1(eng): Audio: pcm_s24le, 48000 Hz, mono, s32, 1152 kb/s (default)
    Metadata:
      creation_time   : 2015-04-14 20:40:41
      handler_name    : Apple Alias Data Handler
      timecode        : 00:00:00:00
      encoder         : Lavc56.26.100 pcm_s24le
    Stream #0:2(eng): Audio: pcm_s24le, 48000 Hz, mono, s32, 1152 kb/s (default)
    Metadata:
      creation_time   : 2015-04-14 20:40:41
      handler_name    : Apple Alias Data Handler
      timecode        : 00:00:00:00
      encoder         : Lavc56.26.100 pcm_s24le
Stream mapping:
  Stream #0:0 -> #0:0 (qtrle (native) -> dnxhd (native))
  Stream #0:1 -> #0:1 (pcm_s16le (native) -> pcm_s24le (native))
  Stream #0:1 -> #0:2 (pcm_s16le (native) -> pcm_s24le (native))
Press [q] to stop, [?] for help
[mxf @ 0x7f9db2806c00] -d10_channelcount requires MXF D-10 and will be ignored/s    
    Last message repeated 1 times
frame=  276 fps= 26 q=1.0 Lsize=  166981kB time=00:00:11.20 bitrate=122134.7kbits/s    
video:163392kB audio:3150kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.263624%

mediainfo 的完整输出。

General
Complete name                            : /NoBackUp/test.mxf
Format                                   : MXF
Format profile                           : OP-1a
Format settings                          : Closed / Complete
File size                                : 163 MiB
Duration                                 : 11s 40ms
Overall bit rate                         : 124 Mbps
Encoded date                             : 0-00-00 00:00:00.000
Writing application                      : FFmpeg OP1a Muxer 56.25.101
Writing library                          : FFmpeg OP1a Muxer 56.25.101

Video
ID                                       : 2
Format                                   : VC-3
Format_Settings_Wrapping                 : Frame
Codec ID                                 : 0D01030102110100-0401020271080000
Duration                                 : 11s 40ms
Bit rate mode                            : Constant
Bit rate                                 : 121 Mbps
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 25.000 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:2
Bit depth                                : 8 bits
Scan type                                : Progressive
Original scan type                       : Interlaced
Original scan order                      : Top Field First
Bits/(Pixel*Frame)                       : 2.339
Stream size                              : 160 MiB (98%)

Audio #1
ID                                       : 3
Format                                   : PCM
Format settings, Endianness              : Little
Format_Settings_Wrapping                 : Frame (AES)
Codec ID                                 : 0D01030102060300
Duration                                 : 11s 40ms
Bit rate mode                            : Constant
Bit rate                                 : 1 152 Kbps
Channel(s)                               : 1 channel
Sampling rate                            : 48.0 KHz
Bit depth                                : 24 bits
Stream size                              : 1.52 MiB (1%)

Audio #2
ID                                       : 4
Format                                   : PCM
Format settings, Endianness              : Little
Format_Settings_Wrapping                 : Frame (AES)
Codec ID                                 : 0D01030102060300
Duration                                 : 11s 40ms
Bit rate mode                            : Constant
Bit rate                                 : 1 152 Kbps
Channel(s)                               : 1 channel
Sampling rate                            : 48.0 KHz
Bit depth                                : 24 bits
Stream size                              : 1.52 MiB (1%)

Other #1
ID                                       : 1
Type                                     : Time code
Format                                   : MXF TC
Time code of first frame                 : 00:10:00:00
Time code settings                       : Striped

Other #2
Type                                     : Time code
Format                                   : SMPTE TC
Muxing mode                              : SDTI
Time code of first frame                 : 00:10:00:00

Answer 1

-flags +ildct 是指示编码器中隔行扫描的正确标志；我认为该标志正在被音频编码器拾取。尝试使用“-flags:v +ildct”强制媒体类型。