Premiere RGB exports produce bad frames - is YV12 a good alternative?

[spicediver10191]

I've long had an issue with exporting lossless RGB files (using both Lagarith and Huffyuv codecs) from my Premiere CS3 projects.

I nearly aways get bad frames, which are very time consuming to remove.

The lossless AVi files I create are master files for encoding my final MP4, Xvid and DVD/Mpeg2 videos. I do a quick preconversion of the master file from RGB to Yv12 with an Avisynth script before encoding to these chosen lossy formats.

So my workflow is:

Various DVD video sources -> frameserved with Avisynth into Premiere CS3 -> export lossless AVI -> Avisynth convert to YV12 -> Encode to various lossless formats -> distribution.

So....I was wondering if instead it's okay to export a lossless YV12 Lagarith or Huffyuv file from Premiere as an alternative? I've tested this and it produces no bad frames. My concern, then, is whether a YV12 master file - instead of an RGB one - will create inferior or troublesome DVD/Mpeg2, MP4 and Xvid encodes?

(BTW, the YV12 lossless avi files are half size of the RGB ones - I asume this is normal?)

Advice much appreciated.

Thanks.

[jagabo]

All the high compression codecs use YV12 internally. So the only difference between RGB export and YV12 export is who does the conversion. They should be nearly identical.

And yes, lossless YV12 will normally be smaller than lossless RGB because YV12 is half the size of RGB (1.5 bytes per pixel vs 3 bytes per pixel).

[spicediver10191]

thanks jagabo.

[edDV]

thanks jagabo.

Why RGB?

RGB save makes sense if the source and project are RGB or for an intermediate save of an effects project. For instance you would save After Effects work in progress to RGB until finished. It all depends on your work flow.

You go to YV12 when you are done with the project.

[spicediver10191]

thanks jagabo.

Why RGB?

RGB save makes sense if the source and project are RGB or for an intermediate save of an effects project. For instance you would save After Effects work in progress to RGB until finished. It all depends on your work flow.

You go to YV12 when you are done with the project.

Good question!

It's because a long time ago I found a handy guide about Avisynth and Premiere editing at animemusicvideos.com which mentioned that you should always export your project in RGB because RGB is the native colorspace of Premiere. Something about making sure everything (ie colours) looks as it should.

I do preserve RGB when I export bits of footage to and from After Effects, but now it seems there's need to stick to RGB for creating a final lossless master file from my Premiere project.

[edDV]

thanks jagabo.

Why RGB?

RGB save makes sense if the source and project are RGB or for an intermediate save of an effects project. For instance you would save After Effects work in progress to RGB until finished. It all depends on your work flow.

You go to YV12 when you are done with the project.

Good question!

It's because a long time ago I found a handy guide about Avisynth and Premiere editing at animemusicvideos.com which mentioned that you should always export your project in RGB because RGB is the native colorspace of Premiere. Something about making sure everything (ie colours) looks as it should.

I do preserve RGB when I export bits of footage to and from After Effects, but now it seems there's need to stick to RGB for creating a final lossless master file from my Premiere project.

Well, it would be a very large file.

You can set an RGB project and Premiere will convert all imported video to RGB tmp files before preview.

More typically, Premiere defaults to a DV project format. In that case, Premiere converts the timeline to RGB when processing is required (e.g. for transitions or filters) but leaves the unprocessed frames as DV (Y,Cb,Cr). If you save a project in process to RGB (720x480i/29.97 lower field first) the entire timeline will be converted to RGB creating very large 4:4:4 uncompressed files if done right (~130GB/hr).

If you save to DV format, the RGB temp files are converted to DV format so the export will be 13 GB/hr.

If you intend to save a project for reload, you need to save the source clips (bins) and the project file. Premiere will re-render the frames used for filters or transitions to RGB when you attempt to preview the timeline. To avoid this re-render, you can save the RGB temp files from the scratch folder along with the bins but these need to be placed back in the scratch disk folder when you reload the project. If you do this, you can preview the project from where you left it.

I often save projects in process this way to an external hard drive. Then I copy the bins back to the same disk folder or RAID location and the temp files to the scratch disk.