mirror of https://github.com/mpv-player/mpv
671 lines
19 KiB
C
671 lines
19 KiB
C
/*
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RoQ A/V decoder for the MPlayer program
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by Mike Melanson
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based on Dr. Tim Ferguson's RoQ document and accompanying source
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code found at:
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http://www.csse.monash.edu.au/~timf/videocodec.html
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include "config.h"
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#include "bswap.h"
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#include "mp_msg.h"
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#include "mp_image.h"
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#define LE_16(x) (le2me_16(*(unsigned short *)(x)))
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#define LE_32(x) (le2me_32(*(unsigned int *)(x)))
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#define CLAMP_S16(x) if (x < -32768) x = -32768; \
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else if (x > 32767) x = 32767;
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#define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
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// RoQ chunk types
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#define RoQ_INFO 0x1001
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#define RoQ_QUAD_CODEBOOK 0x1002
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#define RoQ_QUAD_VQ 0x1011
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#define RoQ_SOUND_MONO 0x1020
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#define RoQ_SOUND_STEREO 0x1021
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#define MAX_ROQ_CODEBOOK_SIZE 256
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// codebook entry for 2x2 vector
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typedef struct
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{
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// upper and lower luminance value pairs of 2x2 vector: [y0 y1], [y2 y3]
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unsigned short v2_y_u;
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unsigned short v2_y_l;
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// chrominance components
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unsigned char u, v;
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// these variables are for rendering a doublesized 8x8 block; e.g.:
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// v2_y_rows12 = [y0 y0 y1 y1]
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// v2_y_rows34 = [y2 y2 y3 y3]
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unsigned long v2d_y_rows_12;
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unsigned long v2d_y_rows_34;
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// ex: v2_u_row1 = [u u]
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// v2_v_row2 = [v v]
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unsigned short v2d_u_rows_12;
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unsigned short v2d_v_rows_12;
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// maintain separate bytes for the luminance values as well
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unsigned char y0, y1, y2, y3;
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} roq_v2_codebook;
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// codebook entry for 4x4 vector
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typedef struct
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{
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unsigned char v2_index[4];
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} roq_v4_codebook;
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typedef struct
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{
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roq_v2_codebook v2[MAX_ROQ_CODEBOOK_SIZE];
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roq_v4_codebook v4[MAX_ROQ_CODEBOOK_SIZE];
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mp_image_t *prev_frame;
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} roqvideo_info;
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// This function fills in the missing information for a v2 vector after
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// loading the Y, U and V values.
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inline void prep_v2(roq_v2_codebook *v2)
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{
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v2->v2_y_u = be2me_16((v2->y0 << 8) | v2->y1);
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v2->v2_y_l = be2me_16((v2->y2 << 8) | v2->y3);
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v2->v2d_y_rows_12 = be2me_32((v2->y0 << 24) | (v2->y0 << 16) |
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(v2->y1 << 8) | v2->y1);
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v2->v2d_y_rows_34 = be2me_32((v2->y2 << 24) | (v2->y2 << 16) |
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(v2->y3 << 8) | v2->y3);
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// no reason to swap these for endianness since they're the same bytes
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v2->v2d_u_rows_12 = (v2->u << 8) | v2->u;
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v2->v2d_v_rows_12 = (v2->v << 8) | v2->v;
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}
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inline void paint_v2double_block(
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unsigned char *y_plane,
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unsigned char *u_plane,
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unsigned char *v_plane,
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roq_v2_codebook *v2,
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unsigned int y_stride,
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unsigned int u_stride,
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unsigned int v_stride)
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{
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// render the luminance components
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*(unsigned int *)y_plane = v2->v2d_y_rows_12;
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y_plane += y_stride;
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*(unsigned int *)y_plane = v2->v2d_y_rows_12;
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y_plane += y_stride;
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*(unsigned int *)y_plane = v2->v2d_y_rows_34;
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y_plane += y_stride;
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*(unsigned int *)y_plane = v2->v2d_y_rows_34;
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// render the color planes
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*(unsigned short *)u_plane = v2->v2d_u_rows_12;
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u_plane += u_stride;
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*(unsigned short *)u_plane = v2->v2d_u_rows_12;
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*(unsigned short *)v_plane = v2->v2d_v_rows_12;
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v_plane += v_stride;
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*(unsigned short *)v_plane = v2->v2d_v_rows_12;
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}
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inline void paint_v4_block(
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unsigned char *y_plane,
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unsigned char *u_plane,
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unsigned char *v_plane,
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unsigned int y_stride,
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unsigned int u_stride,
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unsigned int v_stride,
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roq_v2_codebook *v2_a,
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roq_v2_codebook *v2_b,
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roq_v2_codebook *v2_c,
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roq_v2_codebook *v2_d)
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{
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// render luminance components
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((unsigned short *)y_plane)[0] = v2_a->v2_y_u;
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((unsigned short *)y_plane)[1] = v2_b->v2_y_u;
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y_plane += y_stride;
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((unsigned short *)y_plane)[0] = v2_a->v2_y_l;
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((unsigned short *)y_plane)[1] = v2_b->v2_y_l;
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y_plane += y_stride;
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((unsigned short *)y_plane)[0] = v2_c->v2_y_u;
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((unsigned short *)y_plane)[1] = v2_d->v2_y_u;
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y_plane += y_stride;
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((unsigned short *)y_plane)[0] = v2_c->v2_y_l;
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((unsigned short *)y_plane)[1] = v2_d->v2_y_l;
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// render the color planes
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u_plane[0] = v2_a->u;
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u_plane[1] = v2_b->u;
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u_plane += u_stride;
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u_plane[0] = v2_c->u;
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u_plane[1] = v2_d->u;
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v_plane[0] = v2_a->v;
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v_plane[1] = v2_b->v;
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v_plane += v_stride;
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v_plane[0] = v2_c->v;
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v_plane[1] = v2_d->v;
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}
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// This function copies the 4x4 block from the prev_*_planes to the
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// current *_planes.
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inline void copy_4x4_block(
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unsigned char *y_plane,
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unsigned char *u_plane,
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unsigned char *v_plane,
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unsigned char *prev_y_plane,
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unsigned char *prev_u_plane,
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unsigned char *prev_v_plane,
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unsigned int y_stride,
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unsigned int u_stride,
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unsigned int v_stride)
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{
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int i;
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// copy over the luminance components (4 rows, 1 uint each)
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for (i = 0; i < 4; i++)
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{
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*(unsigned int *)y_plane = *(unsigned int *)prev_y_plane;
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y_plane += y_stride;
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prev_y_plane += y_stride;
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}
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// copy the chrominance values
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for (i = 0; i < 2; i++)
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{
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*(unsigned short*)u_plane = *(unsigned short*)prev_u_plane;
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u_plane += u_stride;
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prev_u_plane += u_stride;
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*(unsigned short*)v_plane = *(unsigned short*)prev_v_plane;
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v_plane += v_stride;
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prev_v_plane += v_stride;
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}
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}
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// This function copies the 8x8 block from the prev_*_planes to the
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// current *_planes.
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inline void copy_8x8_block(
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unsigned char *y_plane,
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unsigned char *u_plane,
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unsigned char *v_plane,
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unsigned char *prev_y_plane,
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unsigned char *prev_u_plane,
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unsigned char *prev_v_plane,
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unsigned int y_stride,
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unsigned int u_stride,
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unsigned int v_stride)
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{
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int i;
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// copy over the luminance components (8 rows, 2 uints each)
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for (i = 0; i < 8; i++)
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{
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((unsigned int *)y_plane)[0] = ((unsigned int *)prev_y_plane)[0];
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((unsigned int *)y_plane)[1] = ((unsigned int *)prev_y_plane)[1];
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y_plane += y_stride;
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prev_y_plane += y_stride;
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}
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// copy the chrominance values
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for (i = 0; i < 4; i++)
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{
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*(unsigned int*)u_plane = *(unsigned int*)prev_u_plane;
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u_plane += u_stride;
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prev_u_plane += u_stride;
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*(unsigned int*)v_plane = *(unsigned int*)prev_v_plane;
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v_plane += v_stride;
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prev_v_plane += v_stride;
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}
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}
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// This function creates storage space for the vector codebooks.
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void *roq_decode_video_init(void)
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{
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roqvideo_info *info =
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(roqvideo_info *)calloc(sizeof(roqvideo_info), 1);
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info->prev_frame = NULL;
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return info;
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}
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#define EMPTY_ROQ_CODEWORD 0xFFFF0000
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#define FETCH_NEXT_CODE() \
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if (current_roq_codeword == EMPTY_ROQ_CODEWORD) \
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{ \
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if (stream_ptr + 2 > encoded_size) \
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{ \
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mp_msg(MSGT_DECVIDEO, MSGL_WARN, \
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"RoQ video: stream pointer just went out of bounds (1)\n"); \
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return; \
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} \
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current_roq_codeword = (0x0000FFFF) | \
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(encoded[stream_ptr + 0] << 16) | \
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(encoded[stream_ptr + 1] << 24); \
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stream_ptr += 2; \
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} \
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roq_code = ((current_roq_codeword >> 30) & 0x03); \
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current_roq_codeword <<= 2;
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#define FETCH_NEXT_ARGUMENT() \
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if (stream_ptr + 1 > encoded_size) \
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{ \
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mp_msg(MSGT_DECVIDEO, MSGL_WARN, \
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"RoQ video: stream pointer just went out of bounds (2)\n"); \
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return; \
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} \
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argument = encoded[stream_ptr++];
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#define CHECK_PREV_FRAME() \
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if (!info->prev_frame) \
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{ \
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mp_msg(MSGT_DECVIDEO, MSGL_WARN, \
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"RoQ video: can't handle motion vector when there's no previous frame\n"); \
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return; \
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}
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void roq_decode_video(void *context, unsigned char *encoded,
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int encoded_size, mp_image_t *mpi)
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{
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roqvideo_info *info = (roqvideo_info *)context;
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int stream_ptr = 0;
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int i, j;
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int chunk_length;
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int v2_count;
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int v4_count;
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int roq_code;
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unsigned int current_roq_codeword = EMPTY_ROQ_CODEWORD;
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unsigned char argument = 0;
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char mean_motion_x;
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char mean_motion_y;
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int mx, my; // for calculating the motion vector
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int mblock_x = 0;
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int mblock_y = 0;
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int quad8_x, quad8_y; // for pointing to 8x8 blocks in a macroblock
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int quad4_x, quad4_y; // for pointing to 4x4 blocks in an 8x8 block
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unsigned char *y_plane;
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unsigned char *u_plane;
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unsigned char *v_plane;
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unsigned char *prev_y_plane;
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unsigned char *prev_u_plane;
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unsigned char *prev_v_plane;
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unsigned int y_stride = mpi->stride[0];
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unsigned int u_stride = mpi->stride[1];
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unsigned int v_stride = mpi->stride[2];
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roq_v4_codebook v4;
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// make sure the encoded chunk is of minimal acceptable length
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if (encoded_size < 8)
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{
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mp_msg(MSGT_DECVIDEO, MSGL_WARN,
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"RoQ video: chunk isn't even 8 bytes long (minimum acceptable length)\n");
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return;
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}
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// make sure the resolution checks out
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if ((mpi->width % 16 != 0) || (mpi->height % 16 != 0))
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{
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mp_msg(MSGT_DECVIDEO, MSGL_WARN,
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"RoQ video resolution: %d x %d; expected dimensions divisible by 16\n");
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return;
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}
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if (LE_16(&encoded[stream_ptr]) == RoQ_QUAD_CODEBOOK)
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{
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stream_ptr += 2;
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chunk_length = LE_32(&encoded[stream_ptr]);
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stream_ptr += 4;
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v4_count = encoded[stream_ptr++];
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v2_count = encoded[stream_ptr++];
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if (v2_count == 0)
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v2_count = 256;
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if ((v4_count == 0) && (v2_count * 6 < chunk_length))
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v4_count = 256;
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// make sure the lengths agree with each other
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if (((v2_count * 6) + (v4_count * 4)) != chunk_length)
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{
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mp_msg(MSGT_DECVIDEO, MSGL_WARN,
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"RoQ video: encountered quad codebook chunk with weird lengths (1)\n");
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return;
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}
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if ((v2_count * 6) > (encoded_size - stream_ptr))
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{
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mp_msg(MSGT_DECVIDEO, MSGL_WARN,
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"RoQ video: encountered quad codebook chunk with weird lengths (2)\n");
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return;
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}
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// load the 2x2 vectors
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for (i = 0; i < v2_count; i++)
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{
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info->v2[i].y0 = encoded[stream_ptr++];
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info->v2[i].y1 = encoded[stream_ptr++];
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info->v2[i].y2 = encoded[stream_ptr++];
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info->v2[i].y3 = encoded[stream_ptr++];
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info->v2[i].u = encoded[stream_ptr++];
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info->v2[i].v = encoded[stream_ptr++];
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prep_v2(&info->v2[i]);
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}
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if ((v4_count * 4) > (encoded_size - stream_ptr))
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{
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mp_msg(MSGT_DECVIDEO, MSGL_WARN,
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"RoQ video: encountered quad codebook chunk with weird lengths (3)\n");
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return;
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}
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// load the 4x4 vectors
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for (i = 0; i < v4_count; i++)
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{
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info->v4[i].v2_index[0] = encoded[stream_ptr++];
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info->v4[i].v2_index[1] = encoded[stream_ptr++];
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info->v4[i].v2_index[2] = encoded[stream_ptr++];
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info->v4[i].v2_index[3] = encoded[stream_ptr++];
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}
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}
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if (LE_16(&encoded[stream_ptr]) == RoQ_QUAD_VQ)
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{
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stream_ptr += 2;
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chunk_length = LE_32(&encoded[stream_ptr]);
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stream_ptr += 4;
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mean_motion_y = encoded[stream_ptr++];
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mean_motion_x = encoded[stream_ptr++];
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// start by copying entire previous frame
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if (info->prev_frame)
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{
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memcpy(mpi->planes[0], info->prev_frame->planes[0],
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mpi->width * mpi->height);
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memcpy(mpi->planes[1], info->prev_frame->planes[1],
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(mpi->width * mpi->height) / 4);
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memcpy(mpi->planes[2], info->prev_frame->planes[2],
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(mpi->width * mpi->height) / 4);
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}
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// iterate through the 16x16 macroblocks
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for (mblock_y = 0; mblock_y < mpi->height; mblock_y += 16)
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{
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for (mblock_x = 0; mblock_x < mpi->width; mblock_x += 16)
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{
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// iterate through the 4 quadrants of the macroblock
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for (i = 0; i < 4; i++)
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{
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quad8_x = mblock_x;
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quad8_y = mblock_y;
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if (i & 0x01) quad8_x += 8;
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if (i & 0x02) quad8_y += 8;
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// set up the planes
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y_plane = mpi->planes[0] + quad8_y * y_stride + quad8_x;
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u_plane = mpi->planes[1] + (quad8_y / 2) * u_stride + (quad8_x / 2);
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v_plane = mpi->planes[2] + (quad8_y / 2) * v_stride + (quad8_x / 2);
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// decide how to handle this 8x8 quad
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FETCH_NEXT_CODE();
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switch(roq_code)
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{
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// 8x8 block is the same as in the previous frame;
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// skip it
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case 0:
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break;
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// 8x8 block is painted with an 8x8 block from the last frame
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// (i.e., motion compensation)
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case 1:
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CHECK_PREV_FRAME();
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// prepare the pointers to the planes in the previous frame
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FETCH_NEXT_ARGUMENT(); // argument contains motion vectors
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// figure out the motion vectors
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mx = quad8_x + 8 - (argument >> 4) - mean_motion_x;
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my = quad8_y + 8 - (argument & 0x0F) - mean_motion_y;
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prev_y_plane = info->prev_frame->planes[0] +
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my * y_stride + mx;
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prev_u_plane = info->prev_frame->planes[1] +
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(my / 2) * u_stride + (mx + 1) / 2;
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prev_v_plane = info->prev_frame->planes[2] +
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(my / 2) * v_stride + (mx + 1) / 2;
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// sanity check before rendering
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copy_8x8_block(
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y_plane,
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u_plane,
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v_plane,
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prev_y_plane,
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prev_u_plane,
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prev_v_plane,
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y_stride,
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u_stride,
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v_stride
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);
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break;
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// 8x8 block is painted with a doublesized 4x4 vector
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case 2:
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FETCH_NEXT_ARGUMENT();
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v4 = info->v4[argument];
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// sanity check before rendering
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// iterate through 4 4x4 blocks
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for (j = 0; j < 4; j++)
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{
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quad4_x = quad8_x;
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quad4_y = quad8_y;
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if (j & 0x01) quad4_x += 4;
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if (j & 0x02) quad4_y += 4;
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// set up the planes
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y_plane = mpi->planes[0] + quad4_y * y_stride + quad4_x;
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u_plane = mpi->planes[1] +
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(quad4_y / 2) * u_stride + (quad4_x / 2);
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v_plane = mpi->planes[2] +
|
|
(quad4_y / 2) * v_stride + (quad4_x / 2);
|
|
|
|
paint_v2double_block(
|
|
y_plane,
|
|
u_plane,
|
|
v_plane,
|
|
&info->v2[v4.v2_index[j]],
|
|
y_stride,
|
|
u_stride,
|
|
v_stride
|
|
);
|
|
}
|
|
break;
|
|
|
|
// 8x8 block is broken down into 4 4x4 blocks and painted using
|
|
// 4 different codes.
|
|
case 3:
|
|
// iterate through 4 4x4 blocks
|
|
for (j = 0; j < 4; j++)
|
|
{
|
|
quad4_x = quad8_x;
|
|
quad4_y = quad8_y;
|
|
if (j & 0x01) quad4_x += 4;
|
|
if (j & 0x02) quad4_y += 4;
|
|
|
|
// set up the planes
|
|
y_plane = mpi->planes[0] + quad4_y * y_stride + quad4_x;
|
|
u_plane = mpi->planes[1] +
|
|
(quad4_y / 2) * u_stride + (quad4_x / 2);
|
|
v_plane = mpi->planes[2] +
|
|
(quad4_y / 2) * v_stride + (quad4_x / 2);
|
|
|
|
// decide how to handle this 4x4 quad
|
|
FETCH_NEXT_CODE();
|
|
switch(roq_code)
|
|
{
|
|
// 4x4 block is the same as in the previous frame;
|
|
// skip it
|
|
case 0:
|
|
break;
|
|
|
|
// 4x4 block is motion compensated from the previous frame
|
|
case 1:
|
|
CHECK_PREV_FRAME();
|
|
// prepare the pointers to the planes in the previous frame
|
|
FETCH_NEXT_ARGUMENT(); // argument contains motion vectors
|
|
|
|
// figure out the motion vectors
|
|
mx = quad4_x + 8 - (argument >> 4) - mean_motion_x;
|
|
my = quad4_y + 8 - (argument & 0x0F) - mean_motion_y;
|
|
|
|
prev_y_plane = info->prev_frame->planes[0] +
|
|
my * y_stride + mx;
|
|
prev_u_plane = info->prev_frame->planes[1] +
|
|
(my / 2) * u_stride + (mx + 1) / 2;
|
|
prev_v_plane = info->prev_frame->planes[2] +
|
|
(my / 2) * u_stride + (mx + 1) / 2;
|
|
|
|
// sanity check before rendering
|
|
copy_4x4_block(
|
|
y_plane,
|
|
u_plane,
|
|
v_plane,
|
|
prev_y_plane,
|
|
prev_u_plane,
|
|
prev_v_plane,
|
|
y_stride,
|
|
u_stride,
|
|
v_stride
|
|
);
|
|
break;
|
|
|
|
// 4x4 block is copied directly from v4 vector table
|
|
case 2:
|
|
FETCH_NEXT_ARGUMENT();
|
|
v4 = info->v4[argument];
|
|
|
|
paint_v4_block(
|
|
y_plane,
|
|
u_plane,
|
|
v_plane,
|
|
y_stride,
|
|
u_stride,
|
|
v_stride,
|
|
&info->v2[v4.v2_index[0]],
|
|
&info->v2[v4.v2_index[1]],
|
|
&info->v2[v4.v2_index[2]],
|
|
&info->v2[v4.v2_index[3]]);
|
|
break;
|
|
|
|
// 4x4 block is built from 4 2x2 vectors
|
|
case 3:
|
|
if (stream_ptr + 4 > encoded_size)
|
|
{
|
|
mp_msg(MSGT_DECVIDEO, MSGL_WARN,
|
|
"RoQ video: stream pointer just went out of bounds (2)\n");
|
|
return;
|
|
}
|
|
paint_v4_block(
|
|
y_plane,
|
|
u_plane,
|
|
v_plane,
|
|
y_stride,
|
|
u_stride,
|
|
v_stride,
|
|
&info->v2[encoded[stream_ptr + 0]],
|
|
&info->v2[encoded[stream_ptr + 1]],
|
|
&info->v2[encoded[stream_ptr + 2]],
|
|
&info->v2[encoded[stream_ptr + 3]]);
|
|
stream_ptr += 4;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// one last sanity check on the way out
|
|
// (apparently, it's not unusual to have 2 bytes left over after decode)
|
|
if (stream_ptr < encoded_size - 2)
|
|
{
|
|
mp_msg(MSGT_DECVIDEO, MSGL_WARN,
|
|
"RoQ video: completed frame decode with bytes left over (%d < %d)\n",
|
|
stream_ptr, encoded_size);
|
|
}
|
|
|
|
// save the current frame as the previous frame for the next iteration
|
|
info->prev_frame = mpi;
|
|
}
|
|
|
|
// Initialize the RoQ audio decoder, which is to say, initialize the table
|
|
// of squares.
|
|
void *roq_decode_audio_init(void)
|
|
{
|
|
short *square_array;
|
|
short square;
|
|
int i;
|
|
|
|
square_array = (short *)malloc(256 * sizeof(short));
|
|
if (!square_array)
|
|
return NULL;
|
|
|
|
for (i = 0; i < 128; i++)
|
|
{
|
|
square = i * i;
|
|
square_array[i] = square;
|
|
square_array[i + 128] = -square;
|
|
}
|
|
|
|
return square_array;
|
|
}
|
|
|
|
int roq_decode_audio(
|
|
unsigned short *output,
|
|
unsigned char *input,
|
|
int encoded_size,
|
|
int channels,
|
|
void *context)
|
|
{
|
|
short *square_array = (short *)context;
|
|
int i;
|
|
int predictor[2];
|
|
int channel_number = 0;
|
|
|
|
// prepare the initial predictors
|
|
if (channels == 1)
|
|
predictor[0] = LE_16(&input[0]);
|
|
else
|
|
{
|
|
predictor[0] = input[1] << 8;
|
|
predictor[1] = input[0] << 8;
|
|
}
|
|
SE_16BIT(predictor[0]);
|
|
SE_16BIT(predictor[1]);
|
|
|
|
// decode the samples
|
|
for (i = 2; i < encoded_size; i++)
|
|
{
|
|
predictor[channel_number] += square_array[input[i]];
|
|
CLAMP_S16(predictor[channel_number]);
|
|
output[i - 2] = predictor[channel_number];
|
|
|
|
// toggle channel
|
|
channel_number ^= channels - 1;
|
|
}
|
|
|
|
// return the number of samples decoded
|
|
return (encoded_size - 2);
|
|
}
|