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SDL_HINT_WAVE_FACT_CHUNK(3) SDL3 FUNCTIONS SDL_HINT_WAVE_FACT_CHUNK(3)

NAME

SDL_HINT_WAVE_FACT_CHUNK - A variable controlling how the fact chunk affects the loading of a WAVE file.

HEADER FILE

Defined in SDL3/SDL_hints.h

SYNOPSIS

#include "SDL3/SDL.h"
#define SDL_HINT_WAVE_FACT_CHUNK   SDL_WAVE_FACT_CHUNK"

DESCRIPTION

The fact chunk stores information about the number of samples of a WAVE file. The Standards Update from Microsoft notes that this value can be used to 'determine the length of the data in seconds'. This is especially useful for compressed formats (for which this is a mandatory chunk) if they produce multiple sample frames per block and truncating the block is not allowed. The fact chunk can exactly specify how many sample frames there should be in this case.

Unfortunately, most application seem to ignore the fact chunk and so SDL ignores it by default as well.

The variable can be set to the following values:

• "truncate" - Use the number of samples to truncate the wave data if the
fact chunk is present and valid.

• "strict" - Like "truncate", but raise an error if the fact chunk is
invalid, not present for non-PCM formats, or if the data chunk doesn't
have that many samples.

• "ignorezero" - Like "truncate", but ignore fact chunk if the number of
samples is zero.

• "ignore" - Ignore fact chunk entirely. (default)

This hint should be set before calling SDL_LoadWAV () or

SDL_LoadWAV_IO ()

AVAILABILITY

This hint is available since SDL 3.0.0.

SDL 3.1.2 Simple Directmedia Layer