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/*
* H263 backend for ffmpeg encoder
* Copyright (c) 2000 Gerard Lantau.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdlib.h>
#include <stdio.h>
#include <netinet/in.h>
#include "common.h"
#include "mpegvideo.h"
#include "h263data.h"
void h263_picture_header(MpegEncContext *s, int picture_number)
{
int format;
align_put_bits(&s->pb);
put_bits(&s->pb, 22, 0x20);
put_bits(&s->pb, 8, ((s->picture_number * 30) / s->frame_rate) & 0xff);
put_bits(&s->pb, 1, 1); /* marker */
put_bits(&s->pb, 1, 0); /* h263 id */
put_bits(&s->pb, 1, 0); /* split screen off */
put_bits(&s->pb, 1, 0); /* camera off */
put_bits(&s->pb, 1, 0); /* freeze picture release off */
if (s->width == 128 && s->height == 96)
format = 1;
else if (s->width == 176 && s->height == 144)
format = 2;
else if (s->width == 352 && s->height == 288)
format = 3;
else if (s->width == 704 && s->height == 576)
format = 4;
else if (s->width == 1408 && s->height == 1152)
format = 5;
else
abort();
put_bits(&s->pb, 3, format);
put_bits(&s->pb, 1, (s->pict_type == P_TYPE));
put_bits(&s->pb, 1, 0); /* unrestricted motion vector: off */
put_bits(&s->pb, 1, 0); /* SAC: off */
put_bits(&s->pb, 1, 0); /* advanced prediction mode: off */
put_bits(&s->pb, 1, 0); /* not PB frame */
put_bits(&s->pb, 5, s->qscale);
put_bits(&s->pb, 1, 0); /* Continuous Presence Multipoint mode: off */
put_bits(&s->pb, 1, 0); /* no PEI */
}
static void h263_encode_block(MpegEncContext *s, DCTELEM *block,
int n);
void h263_encode_mb(MpegEncContext *s,
DCTELEM block[6][64],
int motion_x, int motion_y)
{
int cbpc, cbpy, i, cbp;
if (!s->mb_intra) {
/* compute cbp */
cbp = 0;
for(i=0;i<6;i++) {
if (s->block_last_index[i] >= 0)
cbp |= 1 << (5 - i);
}
if ((cbp | motion_x | motion_y) == 0) {
/* skip macroblock */
put_bits(&s->pb, 1, 1);
return;
}
put_bits(&s->pb, 1, 0); /* mb coded */
cbpc = cbp & 3;
put_bits(&s->pb,
inter_MCBPC_bits[cbpc],
inter_MCBPC_code[cbpc]);
cbpy = cbp >> 2;
cbpy ^= 0xf;
put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
/* motion vectors: zero */
put_bits(&s->pb, 1, 1);
put_bits(&s->pb, 1, 1);
} else {
/* compute cbp */
cbp = 0;
for(i=0;i<6;i++) {
if (s->block_last_index[i] >= 1)
cbp |= 1 << (5 - i);
}
cbpc = cbp & 3;
if (s->pict_type == I_TYPE) {
put_bits(&s->pb,
intra_MCBPC_bits[cbpc],
intra_MCBPC_code[cbpc]);
} else {
put_bits(&s->pb, 1, 0); /* mb coded */
put_bits(&s->pb,
inter_MCBPC_bits[cbpc + 4],
inter_MCBPC_code[cbpc + 4]);
}
cbpy = cbp >> 2;
put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
}
/* encode each block */
for(i=0;i<6;i++) {
h263_encode_block(s, block[i], i);
}
}
static void h263_encode_block(MpegEncContext *s, DCTELEM *block, int n)
{
int level, run, last, i, j, last_index, last_non_zero, sign, alevel;
int code, len;
if (s->mb_intra) {
/* DC coef */
level = block[0];
if (level == 128)
put_bits(&s->pb, 8, 0xff);
else
put_bits(&s->pb, 8, level & 0xff);
i = 1;
} else {
i = 0;
}
/* AC coefs */
last_index = s->block_last_index[n];
last_non_zero = i - 1;
for(;i<=last_index;i++) {
j = zigzag_direct[i];
level = block[j];
if (level) {
run = i - last_non_zero - 1;
last = (i == last_index);
sign = 0;
alevel = level;
if (level < 0) {
sign = 1;
alevel = -level;
}
len = 0;
code = 0; /* only to disable warning */
if (last == 0) {
if (run < 2 && alevel < 13 ) {
len = coeff_tab0[run][alevel-1][1];
code = coeff_tab0[run][alevel-1][0];
} else if (run >= 2 && run < 27 && alevel < 5) {
len = coeff_tab1[run-2][alevel-1][1];
code = coeff_tab1[run-2][alevel-1][0];
}
} else {
if (run < 2 && alevel < 4) {
len = coeff_tab2[run][alevel-1][1];
code = coeff_tab2[run][alevel-1][0];
} else if (run >= 2 && run < 42 && alevel == 1) {
len = coeff_tab3[run-2][1];
code = coeff_tab3[run-2][0];
}
}
if (len != 0) {
code = (code << 1) | sign;
put_bits(&s->pb, len + 1, code);
} else {
/* escape */
put_bits(&s->pb, 7, 3);
put_bits(&s->pb, 1, last);
put_bits(&s->pb, 6, run);
put_bits(&s->pb, 8, level & 0xff);
}
last_non_zero = i;
}
}
}
/* write RV 1.0 compatible frame header */
void rv10_encode_picture_header(MpegEncContext *s, int picture_number)
{
align_put_bits(&s->pb);
put_bits(&s->pb, 1, 1); /* marker */
put_bits(&s->pb, 1, (s->pict_type == P_TYPE));
put_bits(&s->pb, 1, 0); /* not PB frame */
put_bits(&s->pb, 5, s->qscale);
if (s->pict_type == I_TYPE) {
/* specific MPEG like DC coding not used */
}
/* if multiple packets per frame are sent, the position at which
to display the macro blocks is coded here */
put_bits(&s->pb, 6, 0); /* mb_x */
put_bits(&s->pb, 6, 0); /* mb_y */
put_bits(&s->pb, 12, s->mb_width * s->mb_height);
put_bits(&s->pb, 3, 0); /* ignored */
}
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