mem_transfer.c

基于Linux的ffmepg decoder

#include "../global.h"
#include "mem_transfer.h"
#include "decoder.h"
#include "define.h"

/* Function pointers - Initialized in the xvid.c module */

TRANSFER_8TO16COPY_PTR transfer_8to16copy;
TRANSFER_16TO8COPY_PTR transfer_16to8copy;

TRANSFER_8TO16SUB_PTR  transfer_8to16sub;
TRANSFER_8TO16SUB2_PTR transfer_8to16sub2;
TRANSFER_16TO8ADD_PTR  transfer_16to8add;

// ben-mark-04'10/21:	TRANSFER8X8_COPY_PTR transfer8x8_copy;


/*****************************************************************************
 *
 * All these functions are used to transfer data from a 8 bit data array
 * to a 16 bit data array.
 *
 * This is typically used during motion compensation, that's why some
 * functions also do the addition/substraction of another buffer during the
 * so called  transfer.
 *
 ****************************************************************************/

/*
 * SRC - the source buffer
 * DST - the destination buffer
 *
 * Then the function does the 8->16 bit transfer and this serie of operations :
 *
 *    SRC (8bit)  = SRC
 *    DST (16bit) = SRC
 */
void
transfer_8to16copy_c(int16_t * const dst,
					 const uint8_t * const src,
					 uint32_t stride)
{
	uint32_t i, j;

	for (j = 0; j < 8; j++) {
		for (i = 0; i < 8; i++) {
			dst[j * 8 + i] = (int16_t) src[j * stride + i];
		}
	}
}

/*
 * SRC - the source buffer
 * DST - the destination buffer
 *
 * Then the function does the 8->16 bit transfer and this serie of operations :
 *
 *    SRC (16bit) = SRC
 *    DST (8bit)  = max(min(SRC, 255), 0)
 */
void
transfer_16to8copy_c(uint8_t * const dst,
					 const int16_t * const src,
					 uint32_t stride)
{
	uint32_t i, j;

	for (j = 0; j < 8; j++) {
		for (i = 0; i < 8; i++) {
			int16_t pixel = src[j * 8 + i];

			if (pixel < 0) {
				pixel = 0;
			} else if (pixel > 255) {
				pixel = 255;
			}
			dst[j * stride + i] = (uint8_t) pixel;
		}
	}
}




/*
 * C   - the current buffer
 * R   - the reference buffer
 * DCT - the dct coefficient buffer
 *
 * Then the function does the 8->16 bit transfer and this serie of operations :
 *
 *    R   (8bit)  = R
 *    C   (8bit)  = R
 *    DCT (16bit) = C - R
 */
void
transfer_8to16sub_c(int16_t * const dct,
					uint8_t * const cur,
					const uint8_t * ref,
					const uint32_t stride)
{
	uint32_t i, j;

	for (j = 0; j < 8; j++) {
		for (i = 0; i < 8; i++) {
			uint8_t c = cur[j * stride + i];
			uint8_t r = ref[j * stride + i];

			cur[j * stride + i] = r;
			dct[j * 8 + i] = (int16_t) c - (int16_t) r;
		}
	}
}


/*
 * C   - the current buffer
 * R1  - the 1st reference buffer
 * R2  - the 2nd reference buffer
 * DCT - the dct coefficient buffer
 *
 * Then the function does the 8->16 bit transfer and this serie of operations :
 *
 *    R1  (8bit) = R1
 *    R2  (8bit) = R2
 *    C   (8bit) = C
 *    DCT (16bit)= C - min((R1 + R2)/2, 255)
 */
void
transfer_8to16sub2_c(int16_t * const dct,
					 uint8_t * const cur,
					 const uint8_t * ref1,
					 const uint8_t * ref2,
					 const uint32_t stride)
{
	uint32_t i, j;

	for (j = 0; j < 8; j++) {
		for (i = 0; i < 8; i++) {
			uint8_t c = cur[j * stride + i];
			int r = (ref1[j * stride + i] + ref2[j * stride + i] + 1) / 2;

			if (r > 255) {
				r = 255;
			}
			//cur[j * stride + i] = r;
			dct[j * 8 + i] = (int16_t) c - (int16_t) r;
		}
	}
}


/*
 * SRC - the source buffer
 * DST - the destination buffer
 *
 * Then the function does the 16->8 bit transfer and this serie of operations :
 *
 *    SRC (16bit) = SRC
 *    DST (8bit)  = max(min(DST+SRC, 255), 0)
 */
void
transfer_16to8add_c(uint8_t * const dst,
					const int16_t * const src,
					uint32_t stride)
{
	uint32_t i, j;

	for (j = 0; j < 8; j++) {
		for (i = 0; i < 8; i++) {
			int16_t pixel = (int16_t) dst[j * stride + i] + src[j * 8 + i];

			if (pixel < 0) {
				pixel = 0;
			} else if (pixel > 255) {
				pixel = 255;
			}
			dst[j * stride + i] = (uint8_t) pixel;
		}
	}
}
#if 0// ben-mark-04'10/21:	
/*
 * SRC - the source buffer
 * DST - the destination buffer
 *
 * Then the function does the 8->8 bit transfer and this serie of operations :
 *
 *    SRC (8bit) = SRC
 *    DST (8bit) = SRC
 */
void
transfer8x8_copy_c(uint8_t * const dst,
				   const uint8_t * const src,
				   const uint32_t stride)
{
	uint32_t i, j;

	for (j = 0; j < 8; j++) {
		for (i = 0; i < 8; i++) {
			dst[j * stride + i] = src[j * stride + i];
		}
	}
}
#endif
void
transfer_nxm_copy_ben(uint8_t * dst,
				   const uint8_t * src,
				   const int n,
				   const int m)
{
	uint32_t i, j;

	for (j = 0; j < m; j++) {
		for (i = 0; i < n; i++) {
			*(dst ++) = *(src ++);
		}
		dst += (8 - n);
		src += (8 - n);
	}
}
void
transfer8x8_copy_ben(DECODER * const dec,
				int curoffset,
				uint8_t * cur,
				uint8_t * ref,
				int refx,
				int refy)
{
	int refoffset;

	refoffset = ((refx >> 3) + ((int)dec->mb_width * 2) * (refy >> 3)) *SIZE_U;
	transfer_nxm_copy_ben(cur + curoffset,
					ref + refoffset
					+ (refy & 7) * 8 + (refx & 7),
					8 - (refx & 7),
					8 - (refy & 7));
	if ((refx & 7) != 0)
		transfer_nxm_copy_ben(cur + curoffset + (8 - (refx & 7)),
						ref + refoffset + 64 + (refy & 7) * 8,
						refx & 7,
						refy & 7);
	if ((refy & 7) != 0) {
		curoffset += (8 - (refx & 7)) * 8;
		refoffset += (int)dec->mb_width * 2 * SIZE_U;
		transfer_nxm_copy_ben(cur + curoffset,
						ref + refoffset + (refx & 7),
						8 - (refx & 7),
						8 - (refy & 7));
		if ((refx & 7) != 0)
			transfer_nxm_copy_ben(cur + curoffset + (8 - (refx & 7)),
							ref + refoffset + 64,
							8 - (refx & 7),
							8 - (refy & 7));
	}
}