I use Premiere Pro CS3 to import the MPEG2 clips from the camcorder, edit them, and correct their tonality and colors. Then I export the Premiere sequence to uncompressed AVI signpost, with Debugmode FrameServer and it's RGB24 option. Then I use AviSynth to deinterlace, resize, denoise, etc, and frameserve to x264 encoder.
From what I understand, I have to convert to YV12, because those AviSynth filters cannot work with RGB input. But I don't understand how to properly convert from RGB to YV12 in AviSynth. For example, how can I make sure there will not be tonality shifts or color shifts, after the RGB to YV12 conversion ? Or how can I get exactly what I see in Premiere, in terms of tonality and colors, after the conversion to YV12 ?
There are 3 values than can be attributed to the "matrix" parameter from the ConvertToYV12() function:
But what is confusing to me is that, after I analyse the original MPEG2 clips with DGIndex, in the Information window it says:
So, several MPEG2 clips with colormatrix BT.470-2 are imported into Premiere Pro CS3 timeline, some cuts are made, some dip to black transitions are applied, then the Fast Color Corrector is applied on many of the clips, and the Three-Way Color Corrector is added on some clips. In this process:
1. Clips are converted from YCbCr to RGB ? What happens with the original colormatrix ? It converts that too ? From BT.470-2 to something else ?
2. When exporting the sequence to avi signpost, those exported frames have the exact same colormatrix as the frames inside the timeline, wich are displayed in Premiere UI ?
3. How do I determine the proper value for the matrix parameter for "ConvertToYV12()", so that what I see in Premiere UI is what I get after RGB to YV12 conversion ?
4. How do I determine the proper value for the --colormatrix parameter for x264.exe, so that what I see in VirtualDub (from the avs with the RGB to YV12 conversion) is what I get in the H.264 stream ?
From what I understand, I have to convert to YV12, because those AviSynth filters cannot work with RGB input. But I don't understand how to properly convert from RGB to YV12 in AviSynth. For example, how can I make sure there will not be tonality shifts or color shifts, after the RGB to YV12 conversion ? Or how can I get exactly what I see in Premiere, in terms of tonality and colors, after the conversion to YV12 ?
There are 3 values than can be attributed to the "matrix" parameter from the ConvertToYV12() function:
Code:
ConvertToYV12(interlaced=true, matrix="pc.601") # keeps full range [0,255]
# or
ConvertToYV12(interlaced=true, matrix="rec709") # scales to TV range [16,235]
# or
ConvertToYV12(interlaced=true, matrix="pc.709") # keeps full range [0,255]Code:
Colorimetry: BT.470-2 B,G*1. Clips are converted from YCbCr to RGB ? What happens with the original colormatrix ? It converts that too ? From BT.470-2 to something else ?
2. When exporting the sequence to avi signpost, those exported frames have the exact same colormatrix as the frames inside the timeline, wich are displayed in Premiere UI ?
3. How do I determine the proper value for the matrix parameter for "ConvertToYV12()", so that what I see in Premiere UI is what I get after RGB to YV12 conversion ?
4. How do I determine the proper value for the --colormatrix parameter for x264.exe, so that what I see in VirtualDub (from the avs with the RGB to YV12 conversion) is what I get in the H.264 stream ?