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View Full Version : Preparing this Rec.601 YV12 clip for Rec.709 MPEG-2 encoding


fvisagie
11th March 2013, 13:04
Hi All,

I'd appreciate some pointers for processing Rec.601 YV12 footage for Rec.709 MPEG-2 encoding. Much of it is shot outdoors with the background over-exposed to compensate for a darker foreground. According to Histrogram() most frames have invalidly high luma values. Here's a 2-frame sample clip (http://www.mediafire.com/file/7hlhpa9lbfeydpz/DV_encode_test_source.avi).

Whenever RGB conversion becomes necessary in the process, for this kind of luma range which would be the best matrix to convert back and forth with - Rec601 or PC.601? Although I've been able to generate terrible results, I'm not sure how to gauge the better-looking ones, being displayed on a PC monitor at PC range I presume.

In this case which matrix would be best for converting Rec.601 YV12 to Rec.709 for final output - Rec709 or PC.709?

How does one actually convert Rec.601 YV12 to Rec.709 YV12? With Rec.601 YV12 input, ConvertToYV12(matrix="Rec709") fails with

ConvertToYV12: invalid "matrix" parameter (RGB data only)


Does that mean converting Rec.601 YV12 -> Rec.709 YV12 can't be done without an intermediate conversion to say RGB?

Many thanks in advance,
Francois

feisty2
11th March 2013, 13:28
ColorMatrix(mode="Rec.601->Rec.709")

TheSkiller
11th March 2013, 15:47
Maybe add "clamp=0" to keep the super white (>235) areas. :)