Vapoursynth

[Jukus]

Originally Posted by jackoneill

There is some documentation: http://www.vapoursynth.com/doc/

Thank you, I know. But I'm interested, for example, the sequence of applications of filters, I think it is not always obvious. Changing the brightness and color need before QTGMC or after, maybe there is no difference? And other nuances of video processing that I don't know about.

[MeteorRain]

That sounds a bit more than a guide, but more of lesson(s) (of being an encoder).

QTGMC is a deinterlacer so it always comes at early stage (probably after delogo, but that depends also.)

And to us, we never change brightness and color of a mastered work (e.g. when backing up bluray discs). But if it's your own recording, things can be a lot different.

[stax76]

I've been studying some tutorials at realpython.com and noticed the tutorial and vs code format code like so:

def foo(a=1, b=1):

foo(a=1, b=1)

In staxrip there is much avs/vs code that use spaces:

def foo(a = 1, b = 1):

foo(a = 1, b = 1)

What is more common? Is both OK or is one officially discouraged and what about AviSynth?

[ChaosKing]

This looks like the official style guide https://www.python.org/dev/peps/pep-0008/

Seems like def foo(a=1, b=1, ...) is recommended.

[Myrsloik]

Originally Posted by stax76

I've been studying some tutorials at realpython.com and noticed the tutorial and vs code format code like so:

def foo(a=1, b=1):

foo(a=1, b=1)

In staxrip there is much avs/vs code that use spaces:

def foo(a = 1, b = 1):

foo(a = 1, b = 1)

What is more common? Is both OK or is one officially discouraged and what about AviSynth?

Use whatever you like as long as you're consistent.

[aegisofrime]

Gonna post this here as I don't think it deserves it's own thread, but what happen to Stephen R. Savage's post about his optimized MVTools?

[Myrsloik]

Originally Posted by aegisofrime

Gonna post this here as I don't think it deserves it's own thread, but what happen to Stephen R. Savage's post about his optimized MVTools?

It got merged into normal mvtools and will be in the next release.

[ChaosKing]

Does get_read_array() return only "video data" without "meta data or something"?

I was comparing different source filters (ffms2, d2vsource, lsmash, dgdecnv) and noticed something strange with VOB files. I save every hash in a list. If the video file passes the "seek-test" the hashes of every source filters should the same. This was the case with many files.
But for vob files the hashes differ with every source filter. Is there something special with VOB files? I mean they can only be decoded in "one correct" way, right? They look all ok in vsedit...

example log

Seek linear order (hash, PicType, n-Frame)
d653d648d8e6407e507c6eaa0116ebe5 I 0
30ad6c41b89dfd8880a12bde6952e7b2 B 1
5e0cb8bad4ba2ec37b4f4db0d4a65691 P 2
...

#from seek-test.py
def hash_frame(frame):
    md5 = hashlib.md5()
    for plane in range(frame.format.num_planes):
        for line in frame.get_read_array(plane):
            md5.update(line)
    return md5.hexdigest()

[Myrsloik]

Originally Posted by ChaosKing

Does get_read_array() return only "video data" without "meta data or something"?

I was comparing different source filters (ffms2, d2vsource, lsmash, dgdecnv) and noticed something strange with VOB files. I save every hash in a list. If the video file passes the "seek-test" the hashes of every source filters should the same. This was the case with many files.
But for vob files the hashes differ with every source filter. Is there something special with VOB files? I mean they can only be decoded in "one correct" way, right? They look all ok in vsedit...

example log

Seek linear order (hash, PicType, n-Frame)
d653d648d8e6407e507c6eaa0116ebe5 I 0
30ad6c41b89dfd8880a12bde6952e7b2 B 1
5e0cb8bad4ba2ec37b4f4db0d4a65691 P 2
...

#from seek-test.py
def hash_frame(frame):
    md5 = hashlib.md5()
    for plane in range(frame.format.num_planes):
        for line in frame.get_read_array(plane):
            md5.update(line)
    return md5.hexdigest()

It's not strange at all. It wasn't until h.264 the standard required (or even specified for that matter) how the DCT transforms should be done in a bit exact manner.

[ChaosKing]

Originally Posted by Myrsloik

It's not strange at all. It wasn't until h.264 the standard required (or even specified for that matter) how the DCT transforms should be done in a bit exact manner.

Aha, ok good to know.

[Jukus]

What is the difference between ffms2 and lsmas?
I already realized that for mpeg 2 need to use only d2v.

[ChaosKing]

Originally Posted by Jukus

What is the difference between ffms2 and lsmas?
I already realized that for mpeg 2 need to use only d2v.

Both are based on ffmpeg. In addition lsmash has GPU support and can open MP4, MOV, ISO Base Media without creating an extra index.
From experience I would say lsmash is more often frame accurate then ffms2.

[Jukus]

How to specify the path to create the index file for ffms2 and lsmas? That is, if I mount the ISO, then I can not write anything in the same directory.

[ChaosKing]

Originally Posted by Jukus

How to specify the path to create the index file for ffms2 and lsmas? That is, if I mount the ISO, then I can not write anything in the same directory.

It's all explained in the readme https://github.com/FFMS/ffms2/blob/m...ynth.md#source

ffms2.Source("video.mp4", cachefile="video.mp4.ffindex")

I think lsmash does not support a custom cache file path.

EDIT
Seems to be supported https://github.com/HolyWu/L-SMASH-Wo...er/VapourSynth

cachefile (default : source + ".lwi")
                    The filename of the index file (where the indexing data is saved).

[Jukus]

@ChaosKing
Unfortunately, it’s still not clear how this should work, can a specific example be provided?

[ChaosKing]

Originally Posted by Jukus

@ChaosKing
Unfortunately, it’s still not clear how this should work, can a specific example be provided?

import vapoursynth as vs
core = vs.core
clip = core.lsmas.LWLibavSource(source=r"D:\video.mkv", cachefile=r"C:\folderxy\myCacheFile.iwi")
clip.set_output()

[Jukus]

@ChaosKing

vapoursynth.Error: LWLibavSource: Function does not take argument(s) named cachefile

[ChaosKing]

Originally Posted by Jukus

@ChaosKing

Use this version https://github.com/HolyWu/L-SMASH-Works/releases

[Jukus]

Originally Posted by ChaosKing

Use this version https://github.com/HolyWu/L-SMASH-Works/releases

Ok, thanks. But is it possible to make an index without Vapour, as it is done for d2v?

[ChaosKing]

Originally Posted by Jukus

Ok, thanks. But is it possible to make an index without Vapour, as it is done for d2v?

Only ffms2 has an indexer: ffmsindex.exe
Latest version: https://forum.doom9.org/showthread.p...05#post1883905