Convert

From Avisynth wiki

AviSynth+
Up-to-date documentation: https://avisynthplus.readthedocs.io

Convert between any of the color formats that AviSynth supports:

Color format	Image format	Bit depth	Sample ratio	Description
RGB24	interleaved	8	4:4:4	(full chroma)
RGB32	interleaved	8	4:4:4:4	(full chroma + alpha)
YV24 ♦	planar	8	4:4:4	(full chroma)
YV16 ♦	planar	8	4:2:2	(chroma shared between 2 pixels)
YUY2	interleaved	8	4:2:2	(chroma shared between 2 pixels)
YV12	planar	8	4:2:0	(chroma shared between 2x2 pixels)
YV411 ♦	planar	8	4:1:1	(chroma shared between 4 pixels)
Y8 ♦	(both)	8	4:0:0	(no chroma)
(♦ = not supported in AviSynth version 2.58 or below)

AVS+ supports all of the above, plus:

Color format	Image format	Bit depth	Sample ratio	Description
RGB48	interleaved	16	4:4:4	(full chroma)
RGB64	interleaved	16	4:4:4:4	(full chroma + alpha)
RGBPxx	planar	8-16, 32 *	4:4:4	(full chroma)
RGBAPxx	planar	8-16, 32 *	4:4:4:4	(full chroma + alpha)
YUV444Pxx	planar	8-16, 32 *	4:4:4	(full chroma)
YUVA444Pxx	planar	8-16, 32 *	4:4:4:4	(full chroma + alpha)
YUV422Pxx	planar	8-16, 32 *	4:2:2	(chroma shared between 2 pixels)
YUVA422Pxx	planar	8-16, 32 *	4:2:2:4	(chroma shared between 2 pixels + alpha)
YUV420Pxx	planar	8-16, 32 *	4:2:0	(chroma shared between 2x2 pixels)
YUVA420Pxx	planar	8-16, 32 *	4:2:0:4	(chroma shared between 2x2 pixels + alpha)
Y10..Y32	(both)	10-16, 32 *	4:0:0	(no chroma)
* 8-16 = 8,10,12,14,16 bit integer; 32 = 32 bit float

When the target format is the same as the source format, the original clip will be returned unchanged, except for the case of ConvertToYV12 or ConvertToYV16 (and high bit depth variants) where the ChromaInPlacement and ChromaOutPlacement parameters are different, or the target placement is different from the source chroma placement read from _ChromaLocation frame property.

There is no unique way of converting YUV to RGB or vice-versa. There are different conversion matrices in use; the two most common ones are available in AviSynth, namely Rec.601 and Rec.709, plus some others. The following should be correct in most cases (see here for more)
Rec.601 should be used when your source is standard definition (usually defined as smaller than 720p):

ConvertToRGB(clip) (using default "Rec601")

Rec.709 should be used when your source is DVD or HDTV:

ConvertToRGB(clip, matrix="Rec709")

The special-purpose matrices PC.601 and PC.709 keep the range unchanged,

instead of converting between 0_d-255_d RGB and 16_d-235_d YUV, as is the normal practice.

The special-purpose matrix AVERAGE is used for (rarely found) sources with unweighted luma,

where Y = (R + G + B) / 3.

Note ConvertToRGB always converts to RGB32 – unless your source is RGB24, in which case no conversion is done. If you need 24-bit RGB for some reason, use ConvertToRGB24 explicitly.

Use ConvertBackToYUY2 to convert back to YUY2 with minimal color-blurring when you have previously applied a YUY2→RGB conversion.

AVS+ See also ConvertBits to convert between bit depths and/or between full-limited range.

Syntax and Parameters

RGB interleaved

ConvertToRGB(clip [, string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 AVS+ ] )
ConvertToRGB24(clip [, string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 AVS+ ] )
ConvertToRGB32(clip [, string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 AVS+ ] )
ConvertToRGB48(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+
ConvertToRGB64(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+

RGB planar

ConvertToPlanarRGB(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+
ConvertToPlanarRGBA(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+

YUV444

ConvertToYV24(clip [, bool interlaced, string matrix,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 AVS+ ] )
ConvertToYUV444(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+
ConvertToYUVA444(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+

YUV422

ConvertToYV16(clip [, bool interlaced, string matrix,
     string ChromaInPlacement,
     string chromaresample,
     string ChromaOutPlacement, AVS+
     float param1, float param2, float param3 AVS+ ] )
ConvertToYUY2(clip [, bool interlaced, string matrix,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 AVS+ ] )
ConvertToYUV422(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     string ChromaOutPlacement,
     float param1, float param2, float param3 ] ) AVS+
ConvertToYUVA422(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     string ChromaOutPlacement,
     float param1, float param2, float param3 ] ) AVS+

ConvertBackToYUY2(clip [, string matrix ] )

YUV420

ConvertToYV12(clip [, bool interlaced, string matrix,
     string ChromaInPlacement,
     string chromaresample,
     string ChromaOutPlacement,
     float param1, float param2, float param3 AVS+ ] )
ConvertToYUV420(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     string ChromaOutPlacement,
     float param1, float param2, float param3 ] ) AVS+
ConvertToYUVA420(clip, [ string matrix, bool interlaced,
     string ChromaInPlacement,
     string chromaresample,
     string ChromaOutPlacement,
     float param1, float param2, float param3 ] ) AVS+

YUV411

ConvertToYV411(clip [, bool interlaced, string matrix,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 AVS+] )
|ConvertToYUV411(clip [, bool interlaced, string matrix,
     string ChromaInPlacement,
     string chromaresample,
     float param1, float param2, float param3 ] ) AVS+ }}

Y-only

ConvertToY8(clip [, string matrix] )
ConvertToY(clip, [ string matrix ] ) AVS+

Parameter Details

string matrix = "Rec601"

Controls the colour coefficients and scaling factors used in RGB↔YUV conversions.

"Rec601" : Uses Rec.601 coefficients; scale full range [0_d..255_d] RGB ↔ TV range [16_d..235_d] YUV.
"Rec709" : Uses Rec.709 (HD) coefficients; scale full range RGB ↔ TV range YUV.
"Rec2020" : Uses Rec.2020 (UHD) coefficients; scale full range RGB ↔ TV range YUV. AVS+
"PC.2020" : Uses Rec.2020 (UHD) coefficients; keep range unchanged. AVS+
"PC.601" : Uses Rec.601 coefficients; keep range unchanged.
"PC.709" : Uses Rec.709 (HD) coefficients; keep range unchanged.
"Average" : Uses averaged coefficients (the luma becomes the average of the RGB channels); keep range unchanged.

AVS+

New syntax: more matrix string constants with separate full/limited range markers

"matrixname:full_or_limited" where

"matrixname" can be (internal _Matrix integer constant in parenthesys)

"rgb" (0 - AVS_MATRIX_RGB)
"709" (1 - AVS_MATRIX_BT709)
"unspec" (2 - AVS_MATRIX_UNSPECIFIED)
"170m" (6 - AVS_MATRIX_ST170_M)
"240m" (7 - AVS_MATRIX_ST240_M)
"470bg" (5 - AVS_MATRIX_BT470_BG)
"601" (5 - AVS_MATRIX_BT470_BG)
"fcc" (4 - AVS_MATRIX_BT470_M)
"bt470m" (4 - AVS_MATRIX_BT470_M)
"ycgco" (8 - AVS_MATRIX_YCGCO not supported)
"2020ncl" (9 - AVS_MATRIX_BT2020_NCL)
"2020" (9 - AVS_MATRIX_BT2020_NCL)
"2020cl" (10 - AVS_MATRIX_BT2020_CL same as 2020ncl)
"chromacl" (13 - AVS_MATRIX_CHROMATICITY_DERIVED_CL not supported)
"chromancl" (12 - AVS_MATRIX_CHROMATICITY_DERIVED_NCL not supported)
"ictcp" (14 - AVS_MATRIX_ICTCP not supported)

The above "matrix" parameters can be followed by a "full" or "f" and "limited" or "l" or "auto" marker after a ":"

e.g. "709:l" means the same as the old "Rec709"

When there is no limited-ness marker, or is set to "auto" then value of _ColorRange frame property is used

Note: old-style "matrix" parameters are kept, their name indicate the full/limited, except "PC.601" and "PC.709".

For memo and the similar new string

"rec601" same as "470bg:l"
"rec709" "709:l"
"pc.601" and "pc601" "470bg:f" but only if source has _ColorRange = 0 (full)
"pc.709" and "pc709" "709:f" but only if source has _ColorRange = 0 (full)
"average" - kept for compatibility, really it has no standard _Matrix equivalent
"rec2020" "2020cl:l"
"pc.2020" and "pc2020" "2020cl:f" but only if source has _ColorRange = 0 (full)

bool interlaced = false

If true, it is assumed that clip is interlaced; by default, it is assumed to be progressive.

This option is needed because for example, the following (assuming clip is interlaced YV12):

SeparateFields(clip)
ConvertToYUY2
Weave

...is upsampled incorrectly. Instead it is better to use:

ConvertToYUY2(clip, interlaced=true)

Note, interlaced=true has an effect only on YV12↔YUY2 or YV12↔RGB conversions. More about that can be found here.

string ChromaInPlacement = "MPEG2"
string ChromaOutPlacement = "MPEG2"

ChromaInPlacement determines the chroma placement in the clip when converting from YV12 (4:2:0) or YV16 (4:2:2) AVS+.

ChromaOutPlacement determines the chroma placement in the clip when converting to YV12 (4:2:0) or YV16 (4:2:2) AVS+.

The placement can be one of these strings:

"MPEG2" ( AVS+ synonyms: "left")	Subsampling used in MPEG-2 4:2:x and most other formats. Chroma samples are located on the left pixel column of the group (default).
"MPEG1" ( AVS+ synonyms: "jpeg", "center")	Subsampling used in MPEG-1 4:2:0. Chroma samples are located on the center of each group of 4 pixels.
"DV"	Like MPEG-2, but U and V channels are “co-sited” vertically: V on the top row, and U on the bottom row. For 4:1:1, chroma is located on the leftmost column.
"top_left" AVS+	Subsampling used in UHD 4:2:0. Chroma samples are located on the top left pixel column of the group .
"bottom_left" AVS+	4:2:0 only
"bottom" AVS+	4:2:0 only

string chromaresample = "bicubic"

Determines which chroma resampler is used in the conversion. Only used when the chroma resolutions of the source and target are different. All AviSynth resizers are allowed ("point", "bilinear", "bicubic", "lanczos", "lanczos4", "blackman", "spline16", "spline36", "spline64", "gauss", "sinc", "sinpow", "sinclin2" and "userdefined2"). Default is "bicubic". Latter three is for AVS+.

float  param1 = default depends on resampler type
float  param2 = default depends on resampler type
float  param3 = default depends on resampler type

These 'float' type parameters can be the additional parameters for the chroma resamplers. Some resizer algorithms would need and can be fine tuned with up to 3 parameters. Their default values depend on the selected chromaresample resizer kernel,

Notes

Frame properties AVS+

In Avisynth v3.7.1. frame property (_ChromaLocation) support appears in selected filters (e.g. ConvertToYUV422). Property can be read and/or set. A frame property can replace default behaviour of location parameters and is set (or deleted) upon finishing conversion. Since a format without subsampling such as 4:4:4 (YV24) does not have chroma location, the property is deleted automatically when converting to 4:4:4 or RGB.

"ChromaInLocation" rules:

if source has _ChromaLocation frame property it will be used else the default is "mpeg2" ("left")
if parameter is "auto" or not given at all, ChromaInLocation will be set to the above mentioned default value
if parameter is explicitely given, it will be used

"ChromaOutLocation" rules:

default is "mpeg2" ("left")
if parameter is "auto" or not given at all, ChromaOutLocation will be set to the above mentioned default value
if parameter is explicitely given, it will be used

Accepted values for "ChromaInLocation" and "ChromaOutLocation" (when source/target is a chroma subsampled format)

(full list):

"left" or "mpeg2"
"center" or "jpeg" or "mpeg1"
"top_left"
"dv"
"top"
"bottom_left"
"bottom"

_ChromaLocation constants - as seen in propShow()

AVS_CHROMA_LEFT = 0
AVS_CHROMA_CENTER = 1
AVS_CHROMA_TOP_LEFT = 2 (4:2:0 only)
AVS_CHROMA_TOP = 3 (4:2:0 only)
AVS_CHROMA_BOTTOM_LEFT = 4 (4:2:0 only)
AVS_CHROMA_BOTTOM = 5 (4:2:0 only)
AVS_CHROMA_DV = 6 Special to Avisynth

Conversion paths

In v2.60 the following conversion paths occur:

YUV planar → RGB via YV24
YUV planar → YUY2 via YV16

(except for YV12 and chroma options listed above not explicitly set; in that case there is a direct conversion from YV12 to YUY2)

RGB → YUV planar via YV24
YUY2 → YUV planar via YV16

(except for YV12 and chroma options listed above not explicitly set; in that case there is a direct conversion from YUY2 to YV12)

The chroma options chromaresample, ChromaInPlacement and ChromaOutPlacement are only used in the 'planar conversion' part of the conversion path.

Suppose you have a YUY2 clip for example and you convert it to YV24. The YUY2 will be converted to YV16 first without applying the chroma options. Then YV16 will be converted to YV24 while applying chromaresample. Since YV12 is not involved, ChromaInPlacement and ChromaOutPlacement won't be used.

Sampling

[This page] covers the sampling methods and color formats in more detail.

Color conversions

[This page] covers the color conversions in more detail.

Changelog

v3.7.3	Added "sinpow", "sinclin2" and "userdefined2" to chromaresampler options Add "param1", "param2" and "param3" to ConvertToXXXX where 'chromaresample' exists (b,c,s,taps and p parameters can be set, depending on the resizer.) Add ConvertToYUVA420, ConvertToYUVA422, ConvertToYUVA444
v3.7.1	Added ChromaOutPlacement to 4:2:2 related functions Added new matrix constants, optional new syntax Added new chroma location constants Added _ChromaLocation frame property
v2.60	Added ConvertToY8, ConvertToYV411, ConvertToYV16, ConvertToYV24, ChromaInPlacement, ChromaOutPlacement, chromaresample, matrix="AVERAGE".
v2.50	Added ConvertToYV12.

Retrieved from "http://avisynth.nl/index.php?title=Convert&oldid=13425"

Categories:

Convert

Contents

Syntax and Parameters

RGB interleaved

RGB planar

YUV444

YUV422

YUV420

YUV411

Y-only

Parameter Details

Notes

Frame properties AVS+

Conversion paths

Sampling

Color conversions

Changelog

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