yuv_and_pgx_from_ppm

Author: Ismael Seidel Affiliation: Embedded Computing Lab (ECL), Federal University of Santa Catarina (UFSC) Contributors:

  • André Filipe da Silva Fernandes

Description:

This module converts the JPEG Pleno LF Dataset from PPM to YUV and PGX formats. The PGX and YUV files should have the same data. This implementation is for JPEG Pleno CE 14.

checksum_conversion(lightfield_name, md5, file_format, configuration)[source]

Verify MD5 checksum for converted light field files.

Compares computed MD5 hash against expected value stored in configuration. Logs result indicating whether checksum matches or not.

Parameters:

  • lightfield_name (str) – Name of the light field

  • md5 (str) – Computed MD5 hash value

  • file_format (str) – File format (ppm, yuv, or pgx)

  • configuration (ConfigurationReader) – Configuration reader with checksum data

Returns:

None

Return type:

None

Raises:

Exception – If file format is not supported (ppm, yuv, or pgx)

get_output_log()[source]

Get FFmpeg version and initialize conversion output log.

Returns:

Dictionary with FFmpeg version and empty conversion results list

Return type:

dict

Raises:

Exception – If FFmpeg is not available or version check fails

download_lightfield_if_needed(lightfield, configuration)[source]

Download light field PPM files if not already present locally.

Downloads the light field from configured URL and extracts to the appropriate raw_ppm_path directory if files don’t already exist.

Parameters:
Returns:

None

Return type:

None

Raises:

Exception – If URL not configured and files not present

convert_lightfield_to_yuv_and_pgx(lightfield_name, configuration)[source]

Ensure light field is available in PPM, YUV and PGX formats.

Handles all format conversions needed for a light field: - Downloads original format if needed - Preprocesses the raw light field - Converts to PPM format - Converts from PPM to YUV - Converts from YUV to PGX

Parameters:

  • lightfield_name (str) – Name of the light field to convert

  • configuration (ConfigurationReader) – Configuration reader with paths and format settings

Returns:

Dictionary with ‘ppm’, ‘yuv’, and ‘pgx’ light field instances

Return type:

dict

main(configuration=None)[source]

Convert JPEG Pleno light field dataset from PPM to YUV and PGX formats.

Orchestrates the complete format conversion pipeline for all configured light fields. Downloads raw PPM files if needed, preprocesses them, and converts to both YUV and PGX formats with full MD5 checksum verification. Performs round-trip validation (YUV->PGX->YUV) to ensure data integrity.

Usage: python yuv_and_pgx_from_ppm.py <configuration.json>

Parameters:

configuration (ConfigurationReader) – Configuration reader (read from argv if None)

Returns:

None

Return type:

None