Main page — VQMT

This is part of MSU Video Quality Measurement tool Online Help for MSU VQMT 14.0

MSU Video Quality Measurement Tool (MSU VQMT) project:

Main MSU VQMT page on compression.ru
Download & Purchase on compression.ru
Basic information
Online help
Metrics reference
Version history & Changelog

Online help for MSU VQMT 14.0 contents:

Command-line help
VQMT various lists and tables
Usage of VQMT metrics in CLI
Picture types
Configuration description
List of documentation pages for all versions

Content

Content

The configuration is a JSON file that fully specifies VQMT computation settings. It specifies the set of files, the set of metrics, and calculation settings. You can use the configuration file instead of a classical CLI configuration (for any computational purpose, excluding getting help, specification and activation). Using the configuration file is possible in command via the specifying -config option. Also, it is possible to read the configuration JSON from STDIN using -config-stdin. The configuration is available only in the CLI interface in PRO/Premium edition.

version - This configuration file version (optional)
Syntax: [integer,integer]

First integer for major version, second one for minor. Supported versions:
- 12.1
- 13.0
- 13.1
- 14.0
Default: [14,0]
files - List of all input files. The first will be treated as the original one for reference metrics
Syntax: [A, ...]. A possible values: One of:
- “string”
- [“string”, {object}]
The string is always file name. Possible keys for the object:
- mode - (string) - explicit mode for reading a file. See also List of open modes. Default: “auto”
- index - (string) - index mode
- index_file - (string) - index file. For some index modes will be skipped
- props - (object) - additional properties, specific for mode and file (see List of open modes)
- range - (array) - specify array of one element - [N] to skip N frames. Specify array of two elements [N, M] to select frames from N to M inclusive
- stdin - (bool) - specify true, if the file should be read from stdin
- offset_type - (string) - if range specified, the way for seeking target frame
metrics - List of metrics to perform
Syntax: [A, ...]. A possible values: {object}
- metric - Metric to perform
  Syntax:
  
  One of:
  - “string”
  - {“name”:”string”, “device”:”string”}
  - {“name”:”string”, “variation”:”string”}
  Run VQMT with -list json metrics arguments to see the list of all available metrics. Each metric can be uniquely identified by it’s name and variation
- color - The color component to perform metric. You can specify only one component per element.
  
  Syntax: “string”
  
  Run VQMT with -list json metrics arguments to see the list of all available metrics with supported color components
- config - Metric configuration (optional)
  
  Syntax: {object}
  
  Run VQMT with -list json metrics arguments to see the list of all available metrics with available configuration settings
  
  Default: {}
- vis-gamma - Gamma correction value for visualization (optional)
  
  Syntax: null or A, where A possible values: float
  
  Default: null
- vis-colormap - Colormap for visualization (optional)
  
  Syntax: null or A, where A possible values: “string”
  
  Default: null
output - Settings for writing JSON ans CSV files
Syntax: {object}
- enabled - Turn on/off saving output
  Syntax:
  
  One of:
  - true
  - false
  Default: true
- output_directory - Output directory for saving CSV and JSON (supports VQMT environment variables)
  
  Syntax: “string”
  
  Default: “?(InputOriginalDir)”
- name_generation_type - Scheme for default naming of output files (CSV, JSON)
  Syntax:
  
  One of:
  - “prefix”
  - “postfix”
  - “custom”
  Default: “postfix”
- custom_name - Custom name for output files (supports VQMT environment variables). Only considered if the scheme is CUSTOM
  
  Syntax: “string”
  
  Default: “”
- csv_separator - Separator for starting new cell in the output CSV file
  Syntax:
  
  One of:
  - ”;”
  - ”,”
  Default: “,”
- fp_separator - Separator for starting fractional part in floating point numbers for the output CSV file
  Syntax:
  
  One of:
  - ”.”
  - ”,”
  Default: “.”
- save_csv - Turning on/off sabing CSV
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- save_json - Turning on/off saving JSON
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- json_legacy - Switching to JSON format of older VQMT releases. Currently supported: 11
  
  Syntax: integer
  
  Default: 14
- json_file - Explicit name of the JSON file (supports VQMT environment variables). If set and not empty, has a priority over other specifications. It will override custom_name if set
  
  Syntax: “string”
  
  Default: “”
- csv_file - Explicit name of the CSV file (supports VQMT environment variables). If set and not empty, has a priority over other specifications. It will override custom_name if set
  
  Syntax: “string”
  
  Default: “”
- json_stdout - Enabling/disabling saving JSON to STDOUT instead of a file. Do not use with json_file
  Syntax:
  
  One of:
  - true
  - false
  Default: false
vis - Settings for writing visualization
Syntax: {object}
- enabled - Turn on/off saving visualization for all metrics
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- output_directory - Output directory for saving visualization (supports VQMT environment variables)
  
  Syntax: “string”
  
  Default: “?(InputOriginalDir)”
- name_generation_type - Scheme for default naming of visualization files
  Syntax:
  
  One of:
  - “prefix”
  - “postfix”
  - “custom”
  Default: “postfix”
- compressor - Compressor name for visualization files. See also the list of all compressors
  
  Syntax: “string”
  
  Default: “h264”
- preset - Preset for setting compressor mode
  
  Syntax: “string”
  
  Default: “mq”
- caption_position - Place for printing caption over the visualization (if some data are printed)
  Syntax:
  
  One of:
  - “left-top”
  - “left-bottom”
  - “right-top”
  - “right-bottom”
  Default: “left-top”
- write_value - Turning on/off printing metric value on each visualization frame
  Syntax:
  
  One of:
  - true
  - false
  Default: true
- write_frame - Turning on/off printing frame number on each visualization frame
  Syntax:
  
  One of:
  - true
  - false
  Default: true
- gamma - The default gamma correction value for visualization. Can be overwritten by each metric individually by specifying the metric setting
  
  Syntax: float
  
  Default: 1.0000000000000000
- colormap - The default color table for visualization. Can be overwritten by each metric individually by specifying the metric setting
  
  Syntax: “string”
  
  Default: “”
conversion - Settings for interpreting samples of input files
Syntax: {object}
- standard_name - Color standard that will be used to find exact colorspace for files, where metadata not sufficient to specify exact colorspace
  
  Syntax: “string”
  
  Default: “BT.709”
- full_range - Is quantization range PC (full range, 0..255 in case of 8-bit samples). Quantization range will be used to find exact colorspace representation for files, where metadata not sufficient to specify coded data quantization range
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- display_lum - Display luminance for some HDR colorspaces and metrics. This will be treated as the luminance of a maximum white pixel of an input file. This value will be also used in some metrics as maximum. Value is integer in the range 1..10000
  
  Syntax: float
  
  Default: 10000.000000000000
- sample_conv - The way an integer sample will be converted to continuous
  Syntax:
  
  One of:
  - “shift” - 0xFF means 0.996 (255/256)
  - “repeat” - 0xFF means 1.0
  Default: “repeat”
- legacy_mode - Emulation of an old VQMT mode. It affects some metrics and conversion algorithm. Do not use with other settings of this section
  
  Syntax: integer
  
  Default: 0
- disable_UV_upscale - Disabling upscaling of chroma components (U, V for YUV pixtures types) to Y size for subsampled formats (YUV420, YUV422, etc.)
  Syntax:
  
  One of:
  - true
  - false
  Default: false
bad_frames - Settings for bad frames
Syntax: {object}
- enabled - Turn on/off saving visualization for all metrics
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- dir - Directory for saving bad frames (suports VQMT environment variables)
  
  Syntax: “string”
  
  Default: “?(InputOriginalDir)”
- count - Total (maximum) number of bad frames to be saved
  
  Syntax: integer
  
  Default: 10
- distance - The minimum distance that bad frames can be (frames)
  
  Syntax: integer
  
  Default: 0
- type - The criterion for the selection of bad frames
  Syntax:
  
  One of:
  - “origproc”
  - “procproc”
  - “firstbetter”
  - “secondbetter”
  Default: “origproc”
- format - Image format for saving bad frames
  Syntax:
  
  One of:
  - “BMP”
  - “TIFF”
  Default: “TIFF”
- high_threshold_enabled - Is high threshold enabled
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- low_threshold_enabled - Is low threshold enabled
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- high_threshold - High threshold. A frame with a metric value equal to or better than this will never be considered bad
  
  Syntax: float
  
  Default: 0.00000000000000000
- low_threshold - High threshold. A frame with a metric value equal to or worse than this will never be considered bad
  
  Syntax: float
  
  Default: 0.00000000000000000
- naming_type - Scheme for default naming of bad frames image files
  Syntax:
  
  One of:
  - “frame”
  - “file”
  - “custom”
  Default: “frame”
- custom_name - Custom name for bad frames image files (supports VQMT environment variables). Only considered if the scheme is CUSTOM
  
  Syntax: “string”
  
  Default: “”
geometry - Settings for geometry correction
Syntax: {object}
- enabled - Turn on/off geometry correction. If off, all files mush have the same resolution. Also, geometry correstion can be used to downscale inputs for increasing performance
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- size - Target size for resizing or cropping input images
  Syntax:
  
  One of:
  - “orig”
  - “1/2 orig”
  - “1/4 orig”
  - “min”
  - “max”
  - “custom”
  Default: “orig”
- width - Target width if size is custom
  
  Syntax: integer
  
  Default: 1920
- height - Target height if size is custom
  
  Syntax: integer
  
  Default: 1080
- strategy - Strategy, that specifies resampling, cropping and ratio preserving
  Syntax:
  
  One of:
  - “scale”
  - “scale+crop”
  - “crop”
  Default: “scale”
- algorithm - Image resampling algorithm
  Syntax:
  
  One of:
  - “nearest”
  - “bilinear”
  - “bicubic”
  - “lanczos”
  Default: “bicubic”
- antialiasing - Is antialiasing while resampling enabled
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- prefer_ffmpeg - Use FFmpeg scaling algorithm if available. If false, Intel algorithm will be always used
  Syntax:
  
  One of:
  - true
  - false
  Default: true
mask - Mask specification for indication of the most important areas of the image
Syntax: {object}
- mask_type - Type of mask to be aplied
  Syntax: [“string”, “string”]
  
  Possible types:
  - bin black - binary mask, black for ignored areas
  - bin white - binary mask, white for ignored areas
  - 8bit black - 8-bit mask, black for ignored areas
  - 8bit white - 8-bit mask, white for ignored areas
  - incl-rect <rect spec>, excl-rect <rect spec> - mask consists of rectangle (included or excluded). <rect spec> is ;-separated list of measurements in the order: top, right, bottom, left. Each measurement can be pixel value or percent value (floating point) if followed by ‘%’ sign. A negative value can be used to measure from the opposite side.
  Default: [“no”,”mask”]
- mask_file - A mask file if maskType considers a file. Could be static image or video file
  Syntax: One of:
  - “string”
  - [“string”, {object}]
  The string is always file name. Possible keys for the object:
  - mode - (string) - explicit mode for reading a file. See also [List of open modes](info/#list-of-open-modes). Default: “auto”
  - index - (string) - index mode
  - index_file - (string) - index file. For some index modes will be skipped
  - props - (object) - additional properties, specific for mode and file (see [List of open modes](info/#list-of-open-modes))
  - range - (array) - specify array of one element - [N] to skip N frames. Specify array of two elements [N, M] to select frames from N to M inclusive
  - stdin - (bool) - specify true, if the file should be read from stdin
  - offset_type - (string) - if range specified, the way for seeking target frame
  Default: “”
subsampling - Skipping frames for increasing performance
Syntax: {object}
- enabled - Is subsampling enabled. Subsampling could be used for some metrics to skip frames for increasing performance
  Syntax:
  
  One of:
  - true
  - false
  Default: true
- do_target_fps - Whether subsampling takes into account target_fps setting. If false, value for every_nth_frame will be taken for subsampling
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- every_nth_frame - Number of frames that will be skipped after each processed frame plus one. This value will be taken into account only if do_target_fps is False. Value 1 means no subsampling (each 1st frame is processed)
  
  Syntax: integer
  
  Default: 1
- target_fps - Processing FPS, that VQMT will try to achieve skipping frames
  
  Syntax: float
  
  Default: 25.000000000000000
- enable_seek - Allow VQMT seek in the input files. If false, VQMT will read all intermediate frames
  Syntax:
  
  One of:
  - true
  - false
  Default: false
performance - Performance tuning and information
Syntax: {object}
- threads_number - Number of threads for performing VQMT tasks. VQMT can spawn additional threads
  
  Syntax: integer
  
  Default: 0
- slots_number - Number of slots that be allocated for each metric to process files simultaneously. `0` - default value. Increasing this value will slightly increase memory consumption, but can improve concurrency
  
  Syntax: integer
  
  Default: 0
- metric_parallelism - How many instances of a single metric can work simultaneously. `0` - default value. Set small values to reduce memory consumption. High metric parallelism is quite useless if you computing many metrics simultaneously
  
  Syntax: integer
  
  Default: 0
- show_performance - Whether information about VQMT performance will be displayed instead of results
  Syntax:
  
  One of:
  - true
  - false
  Default: false
- forced_length - The expected number of frames (0 to disable). This parameter affects only progress bar
  
  Syntax: integer
  
  Default: 0
verbosity - Verbocity level. Affects on amount of messages, generated by VQMT
Syntax:

One of:
- “silent”
- “default”
- “all”
Default: “default”

This page is automatically generated by 14.0 BETA r12796 on 2022-01-28. In case of any question or suggestion, please mail us: video-measure@compression.ru

28 Jan 2022

Video processing, compression and quality research group Based in MSU Graphics & Media Laboratory

Content

Video processing, compression
and quality research group
Based in MSU Graphics & Media Laboratory