[FFmpeg-devel] SMPTE RP219-2002 color bar test signal

Tim Nicholson nichot20 at yahoo.com
Fri Aug 24 16:38:03 CEST 2012

On 24/08/12 15:15, Stefano Sabatini wrote:
> On date Friday 2012-08-24 12:21:26 +0100, Tim Nicholson encoded:
>> Prior to any work on implementing the above as a lavfi source, I have
>> uploaded to uploads.ffmpeg.org/incoming a single frame .mov in
>> uncompressed uyvy format.
>> This file was generated in the yuv domain using the SMPTE values which
>> are to ITU 709/SMPTE 274M y, cb, cr values.
>> I hope this might find its way into http://samples.ffmpeg.org/ as a
>> useful test source.
> How is that different from the output generated by smptebars?

The lavfi smptebars generates SD standard bars in rgb colourspace with
the -I/Q patches tweaked to be RGB legal. If used to generate files in
yuv colourspace by default ffmpeg will apply ITU-601 matrix conversion
which is also to the SD standard.

The above .mov is a version of the HD standard of the smpte bars using
the HD yuv matrix values (ITU-R709//SMPTE 274M).

As this version now has -I/Q patches that are RGB safe it would be
possible to generate this as a lavfi source. However since the bars are
HD frame size any conversion to yuv should use the 709 matrix values, so
I am wondering how best to proceed with this.


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