AviSynth+ thread Vol.2

[DTL]

What was the reason for such strange matrix ? Wiki says PC-matrix keep range unchanged. But ColorBarsHD already create levels in standard (industry ITU-R/ARIB) narrow range. Additional Levels of 0,255 to 16,235 looks like compress range even more ? Also aditional Levels() make precision and performance lower - may be add one more single-filter 'matrix' to ConvertToRGB() to create 16..235 RGB from 16..235 standard YUV ?

Also using Levels() for >8bit create additional nightmare for users to compute correct params because it is not autoscale.

Also it is good to add into documentation (wiki ?) about PC-matrix only in Convert() do not keep range in 16..235 (as input) but create some distorted RGB decode (above possible compute errors for 8bit in/out) in narrow-like levels if input standard narrow range not additionally compressed with Levels() processing.

"First time for 32 bit"

I see avspmod still release 32bit builds and require 32bit .dll for it. But I think at AVX2 chips users mostly running x64 OS so 32bit builds a not very required. With intrinsics-based SIMD program 32bit builds are easily possible (mostly all instructions have 32bit versions) but may have somehow lower performance because in 32bit mode addressable by instructions register file space is 1/2 of total.

[Rob105]

When opening Avisynth script is there command to get windows open file window to populate variable with the video.

Purpose is i have script that do not change at all, but file i apply script to changes a a lot, i don't want to type file name in script, i want to use windows open file dialog to populate it.

How i apply Avisynth script to all video files in folder, batch?

[FranceBB]

Originally Posted by Rob105

How i apply Avisynth script to all video files in folder, batch?

Let me introduce you to the fantastic world of FFAStrans: https://forum.doom9.org/showthread.php?t=176655
It does exactly what you want in terms of automation.
Just add a watchfolder -> A/V Decoder -> Custom Avisynth Script (doing whatever you want) -> Encoder -> Delivery
works every time.

[DTL]

Originally Posted by poisondeathray

Note that "PC matrices" are not quite the same thing as "Studio RGB", or "limited range RGB" used in broadcast or some NLE's

The equivalent way in avisynth as what's used a Studio RGB NLE (like vegas) for 8bit for that example above would be

ColorBarsHD(640, 480, pixel_type="YV24")
ConvertToYV12()
Levels(0,1,255,16,235)
ConvertToRGB32(chromaresample="point", matrix="rec709")

Y 180,179,16
C 16,181,179
G 16,179,14
M 179,16,181
R 180,16,17
B 15,16,180

There was an old dedicated "studio RGB" function by "trevlac" for avisynth

I tried 2 more plugins for convert: avsresize and fmtc - they both output equal RGB in narrow range and can accept feed from ColorBarsHD directly:

Y 180, 180, 16
C 16, 180, 179
G 16, 180, 15
M 180, 16, 181
R 180, 16, 17
B 16, 16, 180

So it looks only AVS internal 'narrow' matrix is something special and of lowest precision if even feed by 'double-narrow' 8bit YV24.

[poisondeathray]

Originally Posted by DTL

What was the reason for such strange matrix ?

Not sure what the "PC matrix" was originally for. Back then, people didn't know what "studio RGB"/"limited range RGB" was.

Originally Posted by DTL

I tried 2 more plugins for convert: avsresize and fmtc - they both output equal RGB in narrow range and can accept feed from ColorBarsHD directly:

Y 180, 180, 16
C 16, 180, 179
G 16, 180, 15
M 180, 16, 181
R 180, 16, 17
B 16, 16, 180

zimg/avsresize seems better/faster for just about everything in terms of pixel format conversions than internal functions.