[FFmpeg-user] cat advice

[Rick Corteza]

> On Feb 27, 2017, at 5:11 PM, Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
> 
> 2017-02-27 5:15 GMT+01:00 Rick Corteza <rickcorteza at gmail.com>:
> 
>> Prior to joining files with cat I often convert them using
>> ffmpeg -i inputFile -target ntsc-dvd -qscale 5 outputFile
>> to make them similar quality before joining.
> 
>> The problem with doing this is often the aspect ratio even
>> if I use the -aspect flag.
> 
> Please elaborate.
> 
> Carl Eugen


Here is a better explanation:

Original file - http://www.filedropper.com/original_5 <http://www.filedropper.com/original_5>
Converted file - http://www.filedropper.com/test_198 <http://www.filedropper.com/test_198>

Output:

MacBook:~ mahalko$ /Users/mahalko/Desktop/ffmpeg -i /Users/mahalko/Desktop/original.mp4 -target ntsc-dvd -aspect 464:640 -qscale 5 /Users/mahalko/Desktop/test.vob
ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
  built with llvm-gcc 4.2.1 (LLVM build 2336.11.00)
  configuration: --prefix=/Volumes/Ramdisk/sw --enable-gpl --enable-pthreads --enable-version3 --enable-libspeex --enable-libvpx --disable-decoder=libvpx --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-avfilter --enable-libopencore_amrwb --enable-libopencore_amrnb --enable-filters --enable-libgsm --enable-libvidstab --enable-libx265 --disable-doc --arch=x86_64 --enable-runtime-cpudetect
  libavutil      55. 34.101 / 55. 34.101
  libavcodec     57. 64.101 / 57. 64.101
  libavformat    57. 56.101 / 57. 56.101
  libavdevice    57.  1.100 / 57.  1.100
  libavfilter     6. 65.100 /  6. 65.100
  libswscale      4.  2.100 /  4.  2.100
  libswresample   2.  3.100 /  2.  3.100
  libpostproc    54.  1.100 / 54.  1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/mahalko/Desktop/original.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    creation_time   : 2016-12-26T22:07:38.000000Z
    encoder         : Lavf57.56.100
  Duration: 00:00:00.84, start: 0.000000, bitrate: 2326 kb/s
    Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 464x640, 2320 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
    Metadata:
      creation_time   : 2016-12-26T22:07:38.000000Z
      handler_name    : VideoHandler
Please use -q:a or -q:v, -qscale is ambiguous
Output #0, dvd, to '/Users/mahalko/Desktop/test.vob':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.56.101
    Stream #0:0(und): Video: mpeg2video (Main), yuv420p, 720x480 [SAR 29:60 DAR 29:40], q=2-31, 6000 kb/s, 29.97 fps, 90k tbn, 29.97 tbc (default)
    Metadata:
      creation_time   : 2016-12-26T22:07:38.000000Z
      handler_name    : VideoHandler
      encoder         : Lavc57.64.101 mpeg2video
    Side data:
      cpb: bitrate max/min/avg: 9000000/0/6000000 buffer size: 1835008 vbv_delay: -1
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> mpeg2video (native))
Press [q] to stop, [?] for help
frame=   25 fps=0.0 q=5.0 Lsize=     400kB time=00:00:00.76 bitrate=4269.8kbits/s speed=4.16x    
video:388kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 3.068398%
MacBook:~ mahalko$