Premiere export to lossless is not lossless

[Dogway]

I'm trying to input a DV source into Premiere CS6 to edit and then export to lossless to process later with deinterlacing, etc
I compared the output and there is some degradation but I'm not sure where it would come from, deblock attempt maybe? does Premiere work in RGB?
Could it be a difference in decoding DV codec?

Here a comparison of both (70Mb):
http://www.mediafire.com/download/lj8ddaka7zf3agw/Chunks.rar

I did another test loading the output of the correct chunk, and exporting it again (to sort out DV decoding issues) and the new exported Lagarith file was also very different from source.

[poisondeathray]

What kinds of edits are you doing? For cuts type editing, you should be exporting DV-AVI, it's completely lossless (pass through, direct stream copy)

CS6 works with a YUV timeline. Only when you apply RGB filters, RGB transformations, will those sections get converted to RGB (only those sections). (You will see a red render bar over those sections)

[Dogway]

I see, didn't know I could export directly back to DV-AVI, makes kinda sense since its keyframes based.

I'm going to test again but I fear there's something else going on. I'm just doing cuts, currently simply testing the workflow, load and export media.

edit: yes, poisondeathray. Exporting to DV is lossless... this is fine for this project, but I wonder next time. Thanks for help.

[poisondeathray]

Make sure everything is matched, that the video, sequence settings and export settings match. e.g. NTSC 720x480, 29.97, BFF, etc... or (PAL if it's PAL DV) , whatever . You'll know it's working, because nothing is re-rendered, it just passes through (very fast) . If you see red render bar over the sequence, most likely there is a mismatched setting somewhere.

[poisondeathray]

edit: yes, poisondeathray. Exporting to DV is lossless... this is fine for this project, but I wonder next time. Thanks for help.

For other projects, it's only "lossless" in the same colorspace. If you have YUV assets, YUV timeline, and export a YUV lossless format, then yes it will be mathematically lossless. If you apply RGB filters over some sections, those sections will incur the effect of the filter plus RGB transformation. But other sections will still be lossless like the original. This works for sure with UT Video Codec. I've done many tests, difference testing, SSIM etc....

[Dogway]

Yes, thank you, I think I got it, I thought it was P2 DVCPro50 PAL, since my source codec is DVCPro and it's Type2, happens to be P2 is not Type2 (It's a Panasonic camera name), I think my preset is DV - PAL 32Khz.

By the way, looks FFV1 is not supported right?

[Dogway]

Well, it didn't make any difference either. Exporting to DV is ok but to Lagarith still has same issue. I think it's a color matrix and video decoding disparity, but who knows. This can make me switch to another NLE for real.

If you are curious to test, this is a chunk of the original source:
http://www.mediafire.com/download/7755gqbsem0qle3/chunky.avi

[poisondeathray]

Try UT video codec

[Dogway]

Ok, I have it but output is too large. I edited my above post with a chunk of source.
Let me check UT Video.

Edit: UT Video has similar issues, as I said I think this is a decoding, DV decoding issue possibly.

[poisondeathray]

None of your files match. Even when you line them up on the same frame, there are differences

What are "cacho01 vdub.avi" and "cacho02 premiere.avi" supposed to be ? The vdub one isn't lossless either

I gather "chunky.avi" is the original ?

[Dogway]

I wouldn't be asking if they matched, vdub is the output of the encoded source through vdub, premiere is the output of the source encoded to lagarith through Premiere, then I uploaded the source video of both clips in original format DVCpro codec, which matches with the vdub lossless encode.

btw, I observed, the premiere output has brights clipped, original has some overshoot with 255 values that are non existent in the premiere encode anymore.

[poisondeathray]

I wouldn't be asking if they matched

hahaha, but I had to ask... because...

then I uploaded the source video of both clips in original format DVCpro codec, which matches with the vdub lossless encode.

No it doesn't. The vdub version does not match the original. There are differences with a subtract script. What decoder are you using ? / How are you checking

[Dogway]

Are you sure? I checked again and they are identical. I have an action in PS to compare, the result is pitch black (exact).

The Premiere output is different, as I said above it has brights clipped, as if limiter() was applied, but it looks also as it went through some matrix or even color format conversion. If you want I can paste screenshots, but if you can save me the hassle the better...

edit: to answer your question, FFMS2 for avisynth.

edit2: show me your comparison script, I think you might be doing it wrong.

[poisondeathray]

Yes, I'm 100% sure neither of the two are equivalent compared to "chunky.avi" . The vdub might "look" the same to naked eye, but there are differences detected. And the Premiere one is clamped for sure

Some DV decoders can output the wrong colorspace. Use something like ffms2 to ensure everything is decoded correctly in 4:2:0 since it's PAL DV. Make sure the frames are matched up

[Dogway]

Yes, I use FFMS2 since long ago.
Show me your comparison script, I have a hunch it's wrong since the clips are identical.

[poisondeathray]

edit: to answer your question, FFMS2 for avisynth.

edit2: show me your comparison script, I think you might be doing it wrong.

a=ffvideoSource("chunky.avi")
v=ffvideoSource("cacho01 vdub.avi")
p=ffvideoSource("cacho02 premiere.avi")

Subtract(a,v)
Levels(127, 1, 129, 0, 255)

The vdub encode has the 1st frame out of order, so you might have to advance a few, or use trim(2,0) or some similar technique (ie. make sure the frames match on the same frame before you compare)

[Dogway]

Subtract(a,v) matches, plain 134 value grey video through all of it, as expected.

[poisondeathray]

Did I download the wrong video ? Or something wrong with my ffms2 version ?

Even if I switch to AVISource with the lagarith decoder, there are differences detected

[Dogway]

I downloaded my own videos so we are using the same sources, clean the index files... send both source and vdub, but something might be wrong there. What ffms2 version do you use? I use the build of this year's 20/06

[newpball]

I'm trying to input a DV source into Premiere CS6 to edit and then export to lossless to process later with deinterlacing, etc

So you loaded the video, created a sequence using the video as a source, then all you did was cut and trim on the timeline, no filters applied whatsoever, no rescaling, no cropping and then you exported to a lossless format?

[poisondeathray]

Subtract(a,v) matches, plain 134 value grey video through all of it, as expected.

It should be 128, for a non amplifed script. Neutral Grey is 128

e.g. subtract(a,a) should return 128

Did you add the
Levels(127, 1, 129, 0, 255) to amplify the differnces ?

I downloaded my own videos so we are using the same sources, clean the index files... send both source and vdub, but something might be wrong there. What ffms2 version do you use? I use the build of this year's 20/06

I'm using ffms2_r936+55-avs+vsp

[Dogway]

I'm trying to input a DV source into Premiere CS6 to edit and then export to lossless to process later with deinterlacing, etc

So you loaded the video, created a sequence using the video as a source, then all you did was cut and trim on the timeline, no filters applied whatsoever, no rescaling, no cropping and then you exported to a lossless format?

Exactly, I didn't even made a trim, simply set In/Out and exported the section.

e.g. subtract(a,a) should return 128

Did you add the
Levels(127, 1, 129, 0, 255) to amplify the differnces ?

subtract(a,a) gave me 134, as always I wouldn't put my hand for internal functions so I suspected Levels() was doing something nasty, but in any case 134 represents sameness.

If I use mt_makediff(a,b,U=128,v=128), I get 128 in the luma plane. I can check chroma planes too if you give me more time but I'm sure they are exact too.

[Dogway]

Check with this:

a=ffvideoSource("X:\cacho01 vdub.avi")
b=ffvideoSource("X:\chunky.avi")

a=stackhorizontal(a,stackvertical(Utoy(a),Vtoy(a)))
b=stackhorizontal(b,stackvertical(Utoy(b),Vtoy(b)))

mt_makediff(a,b,U=128,v=128)

[poisondeathray]

If you want independent, non avisynth confirmation, here are the per-frame PSNR compare logs by ffmpeg

chunky vs. vdub
chunky vs. chunky

[poisondeathray]

Check with this:

a=ffvideoSource("X:\cacho01 vdub.avi")
b=ffvideoSource("X:\chunky.avi")

a=stackhorizontal(a,stackvertical(Utoy(a),Vtoy(a)))
b=stackhorizontal(b,stackvertical(Utoy(b),Vtoy(b)))

mt_makediff(a,b,U=128,v=128)

differences detected here

[poisondeathray]

I'm thinking there must be a problem with the download. That's the only logical explanation. I'll try downloading it again

[Dogway]

I think you downloaded the mediafire "watch" video, and not data?

[poisondeathray]

I think you downloaded the mediafire "watch" video, and not data?

I downloaded chunks.rar . And I just re-downloaded it along with chunky.avi. Inside chunks.rar were 2 videos, "cacho01 vdub.avi" , and "cacho02 premiere.avi"

I didn't download some re-encoded video version, I used the direct download . I confirmed 2 lagarith videos, and 1 dvsd video

Same result . I tested on 2 different computers with different avisynth configuations and ffms2 versions

I'll see if someone else can check...

[Dogway]

Did it work now?
I think that for a failed benchmark is more likely to get different results than 100% exact results, Id on't know what else to tell except for you to upload chunky.avi so I can compare with mine. Or a third person to check and prove you or me wrong.

[poisondeathray]

No it didn't work. Same results with 2nd time downloading

It must be some corruption in download service or something. Sometimes avisynth can be problematic with ".dll hell" and various versions , but it's extremely unlikely that 2 different testing methods (both ffmpeg and avisynth) on 2 different computers would be wrong... So I'm guessing corrupted file

haha I was going to upload to mediafire, but then I thought... uhmm maybe not LOL

Check both of them, corruption might be in one or both.