[Libav-user] How to obtain display dimensions

[Lyndon Hill]

Hello,

I am having difficulty obtaining the correct dimensions for viewing a video stream.

For example, but not the only video I am having issue with, I am looking at an MPEG transport stream (MTS) from UK FreeView TV (DVB-T).

ffprobe gives

Stream #0:0[0x1a11]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv), 544x576 [SAR 32:17 DAR 16:9], max. 15000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1[0x1a12](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 128 kb/s
Stream #0:2[0x1a13](eng): Audio: mp3 ([3][0][0][0] / 0x0003), 0 channels, s16p (visual impaired)
Stream #0:3[0x1a16](eng): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)


I understand that SAR = Sample Aspect Ratio (the pixel aspect on the camera sensor) and DAR = Display Aspect Ratio (the aspect that should be used for displaying the video).

I assume this means that the anamorphic dimensions are 544x576 and should be displayed at 16:9; i.e. 1024x576.


What is the correct way to access DAR information ?

thanks

Lyndon Hill