mlib_VideoDCT8x8Quantize_S16_U8(3MLIB)

Name

mlib_VideoDCT8x8Quantize_S16_U8 - forward Discrete Cosine Transform (DCT) and quantization

Synopsis

cc [ flag... ] file... –lmlib [ library... ]
#include <mlib.h>

mlib_status mlib_VideoDCT8x8Quantize_S16_U8(
     mlib_s16 coeffs[64], const mlib_u8 *block,
     const mlib_d64 dqtable[64], mlib_s32 stride);

Description

The mlib_VideoDCT8x8Quantize_S16_U8() function computes the forward DCT and then quantizes the DCT coefficients. It's a combination of mlib_VideoDCT8x8_S16_U8() and mlib_VideoQuantize_S16() for better performance.

The source and destination buffer addresses must be 8-byte aligned.

This function can be used in JPEG with 8-bit precision, or in MPEG for the intra mode.

Parameters

The function takes the following arguments:

coeffs

Pointer to the quantized DCT coefficients. Note that coeffs must be 8-byte aligned.

block

Pointer to an 8x8 block. Note that block must be 8-byte aligned.

dqtable

Pointer to the quantization table generated by mlib_VideoQuantizeInit_S16().

stride

Stride in bytes between adjacent rows in the block. Note that stride must be a multiple of eight.

Return Values

The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE Interface Stability Committed MT-Level MT-Safe

See also

mlib_VideoDCT8x8Quantize_S16_S16_B12(3MLIB), mlib_VideoDCT8x8Quantize_S16_S16_B12_NA(3MLIB), mlib_VideoDCT8x8Quantize_S16_U8_NA(3MLIB), mlib_VideoQuantizeInit_S16(3MLIB), attributes(5)