Aspect Ratio Not Performing Properly - MP4

[Black Hole]

I have some MOVs, taken and then exported from an iPad by uploading to iCloud - a very useful side effect being that they get transcoded on the fly (before upload) to MP4 and occupying about one-seventh the space (and a seventh the upload time).

The problem is that when I copy these MP4s to an HDR-FOX, they play at 4:3 instead of 16:9, unless I set the WIDE button to "auto". I used ffmpeg on the command line to change aspect ratio, and appeared to make no difference. I then started looking at MP4Box to do it, and needed to work out the pixel aspect ratios etc, so I had a look at the properties of the original MP4s - and they claim to be 16:9! See below.

Any ideas why this is and what to do about it (without re-encoding)?

===================== General =====================
Complete name               : G:\test_in.mp4
Format                      : MPEG-4
Format profile              : Base Media / Version 2
Codec Id                    : mp42
File size                   : 79.2 MB
Duration (ms)               : 3mn 39s
Total bitrate               : 3 031 Kbps
Encoded date                : UTC 2016-01-09 07:46:23
Tagged date                 : UTC 2016-01-09 07:48:46

===================== Video =====================
Id                          : 2
Format                      : AVC
Format info                 : Advanced Video Codec
Format profile              : Baseline@L3.1
Use of CABAC                : No
RefFrames                   : 1 frame
Format settings - GOP       : M=1, N=30
Codec Id                    : avc1
Codec info                  : Advanced Video Coding
Duration (ms)               : 3mn 39s
Source_Duration/String      : 3mn 39s
Bitrate                     : 2 966 Kbps
Width                       : 1 280 pixels
Height                      : 720 pixels
Aspect ratio                : 16:9
Framerate mode              : Variable
Framerate                   : 29.970 fps
FrameRate_Minimum/String    : 28.571 fps
FrameRate_Maximum/String    : 30.000 fps
Colorimetry                 : YUV
Colos space                 : 4:2:0
Bit depth                   : 8 bits
Scan type                   : Progressive
Bits/(Pixel*Frame)          : 0.107
Stream size                 : 77.4 MB (98%)
Source_StreamSize/String    : 77.4 MB (98%)
Title                       : Core Media Video
Encoded date                : UTC 2016-01-09 07:46:23
Tagged date                 : UTC 2016-01-09 07:48:46
colour_primaries            : BT.709
transfer_characteristics    : BT.709
matrix_coefficients         : BT.709

===================== Audio =====================
Id                          : 1
Format                      : AAC
Format info                 : Advanced Audio Codec
Format profile              : LC
Codec Id                    : 40
Duration (ms)               : 3mn 39s
Source_Duration/String      : 3mn 39s
Bitrate mode                : Constant
Bitrate                     : 64.0 Kbps
Channel(s)                  : 2 channels
Channel(s)_Original/String  : 1 channel
ChannelPositions            : Front: C
Sampling rate               : 44.1 KHz
Compression_Mode/String     : Lossy
Stream size                 : 1.64 MB (2%)
Source_StreamSize/String    : 1.64 MB (2%)
Title                       : Core Media Audio
Encoded date                : UTC 2016-01-09 07:46:23
Tagged date                 : UTC 2016-01-09 07:48:46

 

[Black Hole]

Every media player I've thrown this at on the PC get it right. What's with the sodding Humax? Maybe it's just not worth worrying about.

 

[prpr]

What does ffprobe say about SAR and DAR?

 

[Black Hole]

I can't see anything about those:

HDRFOX4# ffprobe test_in.mp4
ffprobe version 0.10 Copyright (c) 2007-2012 the FFmpeg developers
  built on Feb 29 2012 10:25:07 with gcc 4.2.0 20070124 (prerelease) - BRCM 11ts-20090508
  configuration: --cross-prefix=mipsel-linux- --enable-cross-compile --arch=mipsel --target-os=linux --enable-gpl --enable-libmp3lame --disable-static --enable-shared --disable-asm --prefix=/mod --extra-cflags=-fPIC
  libavutil      51. 34.101 / 51. 34.101
  libavcodec     53. 60.100 / 53. 60.100
  libavformat    53. 31.100 / 53. 31.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 60.100 /  2. 60.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
  libpostproc    52.  0.100 / 52.  0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test_in.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 1
    compatible_brands: mp41mp42isom
    creation_time   : 2016-01-09 07:46:23
  Duration: 00:03:39.05, start: 0.000000, bitrate: 3031 kb/s
    Stream #0:0(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, mono, s16, 62 kb/s
    Metadata:
      creation_time   : 2016-01-09 07:46:23
      handler_name    : Core Media Audio
    Stream #0:1(und): Video: h264 (Baseline) (avc1 / 0x31637661), yuv420p, 1280x720, 2965 kb/s, 29.96 fps, 29.97 tbr, 600 tbn, 1200 tbc
    Metadata:
      creation_time   : 2016-01-09 07:46:23
      handler_name    : Core Media Video

HDRFOX4#

 

[Black Hole]

Anybody got any more ideas? If nothing else, it will help to further characterise the performance of the Humax codecs.

How can I get the SAR and DAR for this file?

 

[andyk]

If you're still after this, you need to tell ffprobe what you want. I think what you're after is

ffprobe -v error -pretty -select_streams v -show_entries stream=display_aspect_ratio,sample_aspect_ratio,width,height,coded_width,coded_height <name of file>

 

[Black Hole]

Thanks, I'll pick this up again.