ld chroma decoder
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This application takes the output of ld-decode (a PAL or NTSC TBC file) and performs chroma decoding (i.e. colourises it).
The output is a sequence of RGB48, YUV444P16, or GRAY16 video frames suitable for piping to an external application such as FFmpeg.
Syntax:
ld-chroma-decoder [options] <input TBC file name> [output file name]
Note
This is mostly automated with FFmpeg profiles today with tbc-video-export.
.tbc --> Chroma-Decoder y4m --> Pipe | --> FFmpeg --> V210 4:2:2 Uncompressed in the QuickTime MOV container.
NTSC
ld-chroma-decoder --decoder ntsc3d -p y4m -q INPUT.tbc| ffmpeg -i - -c:v v210 -f mov -top 1 -vf setfield=tff -flags +ilme+ildct -pix_fmt yuv422p10le -color_primaries smpte170m -color_trc bt709 -colorspace smpte170m -color_range tv -vf setdar=4/3,setfield=tff OUTPUT.mov
PAL
ld-chroma-decoder --decoder transform3d -p y4m -q INPUT.tbc| ffmpeg -i - -c:v v210 -f mov -top 1 -vf setfield=tff -flags +ilme+ildct -pix_fmt yuv422p10le -color_primaries bt470bg -color_trc bt709 -colorspace bt470bg -color_range tv -vf setdar=4/3,setfield=tff OUTPUT.mov
Y4M Only.
NTSC
ld-chroma-decoder --ffll 1 --lfll 259 --ffrl 2 --lfrl 525 --decoder ntsc3d -p y4m -q INPUT.tbc OUTPUT.mov
PAL
ld-chroma-decoder --ffll 2 --lfll 308 --ffrl 2 --lfrl 620 --decoder transform3d -p y4m -q INPUT.tbc OUTPUT.mov
Most options have a corresponding setting in ld-analyse's 'Chroma decoder configuration' window so you can experiment with them interactively there. For more information, see the ld-analyse manual.
The mono filter treats the whole signal as luma, so it's the best choice when you know that the input video doesn't contain any colour information (e.g. black-and-white films).
--first-active-field-line int, --ffll int
The first visible line of a field.
Ranges:
| Format | Range | Default |
|---|---|---|
| NTSC | 1 - 259 | 20 |
| PAL | 2 - 308 | 22 |
--last-active-field-line int, --lfll int
The last visible line of a field.
Ranges:
| Format | Range | Default |
|---|---|---|
| NTSC | 1 - 259 | 259 |
| PAL | 2 - 308 | 308 |
--first-active-frame-line int, --ffrl int
The first visible line of a field.
Ranges:
| Format | Range | Default |
|---|---|---|
| NTSC | 1 - 525 | 40 |
| PAL | 2 - 620 | 44 |
--last-active-frame-line int, --lfrl int
The last visible line of a field.
Ranges:
| Format | Range | Default |
|---|---|---|
| NTSC | 1 - 525 | 525 |
| PAL | 2 - 620 | 620 |
--chroma-decoder-luma decoder
Chroma decoder to use for the luma instance.
Caution
It is unlikely you need to adjust this.
Available decoders:
| Format | Decoder | Default |
|---|---|---|
| B/W | MONO |
LUMA |
| PAL | PAL2D |
|
| PAL | TRANSFORM2D |
|
| PAL | TRANSFORM3D |
|
| NTSC | NTSC1D |
|
| NTSC | NTSC2D |
|
| NTSC | NTSC3D |
|
| NTSC | NTSC3DNOADAPT |
--chroma-decoder decoder
Chroma decoder to use.
Available decoders:
| Format | Decoder | Default |
|---|---|---|
| B/W | MONO |
LUMA |
| PAL | PAL2D |
PAL/PAL-M |
| PAL | TRANSFORM2D |
|
| PAL | TRANSFORM3D |
PAL CVBS/LD |
| NTSC | NTSC1D |
|
| NTSC | NTSC2D |
NTSC |
| NTSC | NTSC3D |
NTSC CVBS |
| NTSC | NTSC3DNOADAPT |
--chroma-gain 0
Gain factor applied to chroma components normally you will not adjust this over 1~3 in value.
--chroma-phase float
Phase rotation applied to chroma components (degrees 0~360).
--luma-nr float
Luma noise reduction level in dB.
Caution
It is unlikely you need to adjust this.
We recommend applying noise reduction in post via avisynth. vapoursynth or tools like Resolve.
Options:
-h, --help Displays help on commandline
options.
--help-all Displays help including Qt
specific options.
-v, --version Displays version information.
-d, --debug Show debug
-q, --quiet Suppress info and warning
messages
--input-json <filename> Specify the input JSON file
(default input.json)
-s, --start <number> Specify the start frame number
-l, --length <number> Specify the length (number of
frames to process)
-r, --reverse Reverse the field order to
second/first (default
first/second)
--chroma-gain <number> Gain factor applied to chroma
components (default 1.0)
--chroma-phase <number> Phase rotation applied to chroma
components (degrees; default 0.0)
-p, --output-format <output-format> Output format (rgb, yuv, y4m;
default rgb); RGB48, YUV444P16,
GRAY16 pixel formats are supported
-b, --blackandwhite Output in black and white
--pad, --output-padding <number> Pad the output frame to a
multiple of this many pixels on
both axes (1 means no padding,
maximum is 32)
-f, --decoder <decoder> Decoder to use (pal2d,
transform2d, transform3d, ntsc1d,
ntsc2d, ntsc3d, ntsc3dnoadapt,
mono; default automatic)
-t, --threads <number> Specify the number of concurrent
threads (default number of logical
CPUs)
--ffll, --first_active_field_line <number> The first visible line of a
field. Range 1-259 for NTSC
(default: 20), 2-308 for PAL
(default: 22)
--lfll, --last_active_field_line <number> The last visible line of a field.
Range 1-259 for NTSC (default:
259), 2-308 for PAL (default: 308)
--ffrl, --first_active_frame_line <number> The first visible line of a
frame. Range 1-525 for NTSC
(default: 40), 1-620 for PAL
(default: 44)
--lfrl, --last_active_frame_line <number> The last visible line of a frame.
Range 1-525 for NTSC (default:
525), 1-620 for PAL (default: 620)
-o, --oftest NTSC: Overlay the adaptive filter
map (only used for testing)
--chroma-nr <number> NTSC: Chroma noise reduction
level in dB (default 0.0)
--luma-nr <number> Luma noise reduction level in dB
(default 1.0)
--ntsc-phase-comp NTSC: Adjust phase per-line using
burst phase
--simple-pal Transform: Use 1D UV filter
(default 2D)
--transform-threshold <number> Transform: Uniform similarity
threshold (default 0.4)
--transform-thresholds <file> Transform: File containing
per-bin similarity thresholds
--show-ffts Transform: Overlay the input and
output FFTs
Arguments:
input Specify input TBC file (- for piped input)
output Specify output file (omit or - for piped output)
- Basic usage
- TBC Video Export
- PAL decode guide
- NTSC decode guide
- Working with multiple discs
- Working with subtitles
- Archiving LaserActive Discs
- Disc images to download
- ld-decode
- ld-analyse
- ld-chroma-decoder
- ld-process-vbi
- ld-export-metadata
- ld-dropout-correct
- ld-process-efm
- ld-discmap
- ld-disc-stacker
- ld-process-vits
- ld-lds-converter
- ld-chroma-encoder
- efm-decoder