ffmpeg/libavcodec/dv.c

958 lines
28 KiB
C

/*
* DV decoder
* Copyright (c) 2002 Fabrice Bellard.
*
* DV encoder
* Copyright (c) 2003 Roman Shaposhnik.
*
* Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
* of DV technical info.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/**
* @file dv.c
* DV codec.
*/
#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
#include "simple_idct.h"
#include "dvdata.h"
typedef struct DVVideoDecodeContext {
const DVprofile* sys;
AVFrame picture;
uint8_t dv_zigzag[2][64];
uint8_t dv_idct_shift[2][22][64];
uint8_t dv_dct_shift[2][22][64];
void (*get_pixels)(DCTELEM *block, const uint8_t *pixels, int line_size);
void (*fdct[2])(DCTELEM *block);
void (*idct_put[2])(uint8_t *dest, int line_size, DCTELEM *block);
GetBitContext gb;
DCTELEM block[5*6][64] __align8;
} DVVideoDecodeContext;
#define TEX_VLC_BITS 9
/* XXX: also include quantization */
static RL_VLC_ELEM *dv_rl_vlc[1];
static VLC_TYPE dv_vlc_codes[15][23];
static void dv_build_unquantize_tables(DVVideoDecodeContext *s, uint8_t* perm)
{
int i, q, j;
/* NOTE: max left shift is 6 */
for(q = 0; q < 22; q++) {
/* 88DCT */
for(i = 1; i < 64; i++) {
/* 88 table */
j = perm[i];
s->dv_idct_shift[0][q][j] =
dv_quant_shifts[q][dv_88_areas[i]] + 1;
s->dv_dct_shift[0][q][i] =
dv_quant_shifts[q][dv_88_areas[ff_zigzag_direct[i]]] + 4;
}
/* 248DCT */
for(i = 1; i < 64; i++) {
/* 248 table */
s->dv_idct_shift[1][q][i] =
dv_quant_shifts[q][dv_248_areas[i]] + 1;
s->dv_dct_shift[1][q][i] =
dv_quant_shifts[q][dv_248_areas[ff_zigzag248_direct[i]]] + 4;
}
}
}
static int dvvideo_init(AVCodecContext *avctx)
{
DVVideoDecodeContext *s = avctx->priv_data;
DSPContext dsp;
static int done=0;
int i;
if (!done) {
int i;
VLC dv_vlc;
done = 1;
/* NOTE: as a trick, we use the fact the no codes are unused
to accelerate the parsing of partial codes */
init_vlc(&dv_vlc, TEX_VLC_BITS, NB_DV_VLC,
dv_vlc_len, 1, 1, dv_vlc_bits, 2, 2);
dv_rl_vlc[0] = av_malloc(dv_vlc.table_size * sizeof(RL_VLC_ELEM));
for(i = 0; i < dv_vlc.table_size; i++){
int code= dv_vlc.table[i][0];
int len = dv_vlc.table[i][1];
int level, run;
if(len<0){ //more bits needed
run= 0;
level= code;
} else if (code == (NB_DV_VLC - 1)) {
/* EOB */
run = 0;
level = 256;
} else {
run= dv_vlc_run[code] + 1;
level= dv_vlc_level[code];
}
dv_rl_vlc[0][i].len = len;
dv_rl_vlc[0][i].level = level;
dv_rl_vlc[0][i].run = run;
}
memset(dv_vlc_codes, 0xff, sizeof(dv_vlc_codes));
for (i = 0; i < NB_DV_VLC - 1; i++) {
if (dv_vlc_run[i] < 15 && dv_vlc_level[i] < 23 && dv_vlc_len[i] < 15)
dv_vlc_codes[dv_vlc_run[i]][dv_vlc_level[i]] = i;
}
}
/* Generic DSP setup */
dsputil_init(&dsp, avctx);
s->get_pixels = dsp.get_pixels;
/* 88DCT setup */
s->fdct[0] = dsp.fdct;
s->idct_put[0] = dsp.idct_put;
for (i=0; i<64; i++)
s->dv_zigzag[0][i] = dsp.idct_permutation[ff_zigzag_direct[i]];
/* 248DCT setup */
s->fdct[1] = dsp.fdct248;
s->idct_put[1] = simple_idct248_put; // FIXME: need to add it to DSP
memcpy(s->dv_zigzag[1], ff_zigzag248_direct, 64);
/* XXX: do it only for constant case */
dv_build_unquantize_tables(s, dsp.idct_permutation);
/* FIXME: I really don't think this should be here */
if (dv_codec_profile(avctx))
avctx->pix_fmt = dv_codec_profile(avctx)->pix_fmt;
avctx->coded_frame = &s->picture;
return 0;
}
// #define VLC_DEBUG
typedef struct BlockInfo {
const uint8_t *shift_table;
const uint8_t *scan_table;
uint8_t pos; /* position in block */
uint8_t eob_reached; /* true if EOB has been reached */
uint8_t dct_mode;
uint8_t partial_bit_count;
uint16_t partial_bit_buffer;
int shift_offset;
} BlockInfo;
/* block size in bits */
static const uint16_t block_sizes[6] = {
112, 112, 112, 112, 80, 80
};
#ifndef ALT_BITSTREAM_READER
#warning only works with ALT_BITSTREAM_READER
#endif
/* decode ac coefs */
static void dv_decode_ac(DVVideoDecodeContext *s,
BlockInfo *mb, DCTELEM *block, int last_index)
{
int last_re_index;
int shift_offset = mb->shift_offset;
const uint8_t *scan_table = mb->scan_table;
const uint8_t *shift_table = mb->shift_table;
int pos = mb->pos;
int level, pos1, sign, run;
int partial_bit_count;
#ifndef ALT_BITSTREAM_READER //FIXME
int re_index=0;
int re1_index=0;
#endif
OPEN_READER(re, &s->gb);
#ifdef VLC_DEBUG
printf("start\n");
#endif
/* if we must parse a partial vlc, we do it here */
partial_bit_count = mb->partial_bit_count;
if (partial_bit_count > 0) {
uint8_t buf[4];
uint32_t v;
int l, l1;
GetBitContext gb1;
/* build the dummy bit buffer */
l = 16 - partial_bit_count;
UPDATE_CACHE(re, &s->gb);
#ifdef VLC_DEBUG
printf("show=%04x\n", SHOW_UBITS(re, &s->gb, 16));
#endif
v = (mb->partial_bit_buffer << l) | SHOW_UBITS(re, &s->gb, l);
buf[0] = v >> 8;
buf[1] = v;
#ifdef VLC_DEBUG
printf("v=%04x cnt=%d %04x\n",
v, partial_bit_count, (mb->partial_bit_buffer << l));
#endif
/* try to read the codeword */
init_get_bits(&gb1, buf, 4*8);
{
OPEN_READER(re1, &gb1);
UPDATE_CACHE(re1, &gb1);
GET_RL_VLC(level, run, re1, &gb1, dv_rl_vlc[0],
TEX_VLC_BITS, 2);
l = re1_index;
CLOSE_READER(re1, &gb1);
}
#ifdef VLC_DEBUG
printf("****run=%d level=%d size=%d\n", run, level, l);
#endif
/* compute codeword length */
l1 = (level != 256 && level != 0);
/* if too long, we cannot parse */
l -= partial_bit_count;
if ((re_index + l + l1) > last_index)
return;
/* skip read bits */
last_re_index = 0; /* avoid warning */
re_index += l;
/* by definition, if we can read the vlc, all partial bits
will be read (otherwise we could have read the vlc before) */
mb->partial_bit_count = 0;
UPDATE_CACHE(re, &s->gb);
goto handle_vlc;
}
/* get the AC coefficients until last_index is reached */
for(;;) {
UPDATE_CACHE(re, &s->gb);
#ifdef VLC_DEBUG
printf("%2d: bits=%04x index=%d\n",
pos, SHOW_UBITS(re, &s->gb, 16), re_index);
#endif
last_re_index = re_index;
GET_RL_VLC(level, run, re, &s->gb, dv_rl_vlc[0],
TEX_VLC_BITS, 2);
handle_vlc:
#ifdef VLC_DEBUG
printf("run=%d level=%d\n", run, level);
#endif
if (level == 256) {
if (re_index > last_index) {
cannot_read:
/* put position before read code */
re_index = last_re_index;
mb->eob_reached = 0;
break;
}
/* EOB */
mb->eob_reached = 1;
break;
} else if (level != 0) {
if ((re_index + 1) > last_index)
goto cannot_read;
sign = SHOW_SBITS(re, &s->gb, 1);
level = (level ^ sign) - sign;
LAST_SKIP_BITS(re, &s->gb, 1);
pos += run;
/* error */
if (pos >= 64) {
goto read_error;
}
pos1 = scan_table[pos];
level = level << (shift_table[pos1] + shift_offset);
block[pos1] = level;
// printf("run=%d level=%d shift=%d\n", run, level, shift_table[pos1]);
} else {
if (re_index > last_index)
goto cannot_read;
/* level is zero: means run without coding. No
sign is coded */
pos += run;
/* error */
if (pos >= 64) {
read_error:
#if defined(VLC_DEBUG) || 1
fprintf(stderr, "error pos=%d\n", pos);
#endif
/* for errors, we consider the eob is reached */
mb->eob_reached = 1;
break;
}
}
}
CLOSE_READER(re, &s->gb);
mb->pos = pos;
}
static inline void bit_copy(PutBitContext *pb, GetBitContext *gb, int bits_left)
{
while (bits_left >= 16) {
put_bits(pb, 16, get_bits(gb, 16));
bits_left -= 16;
}
if (bits_left > 0) {
put_bits(pb, bits_left, get_bits(gb, bits_left));
}
}
/* mb_x and mb_y are in units of 8 pixels */
static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
uint8_t *buf_ptr1,
const uint16_t *mb_pos_ptr)
{
int quant, dc, dct_mode, class1, j;
int mb_index, mb_x, mb_y, v, last_index;
DCTELEM *block, *block1;
int c_offset, bits_left;
uint8_t *y_ptr;
BlockInfo mb_data[5 * 6], *mb, *mb1;
void (*idct_put)(uint8_t *dest, int line_size, DCTELEM *block);
uint8_t *buf_ptr;
PutBitContext pb, vs_pb;
uint8_t mb_bit_buffer[80 + 4]; /* allow some slack */
int mb_bit_count;
uint8_t vs_bit_buffer[5 * 80 + 4]; /* allow some slack */
int vs_bit_count;
memset(s->block, 0, sizeof(s->block));
/* pass 1 : read DC and AC coefficients in blocks */
buf_ptr = buf_ptr1;
block1 = &s->block[0][0];
mb1 = mb_data;
init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80);
vs_bit_count = 0;
for(mb_index = 0; mb_index < 5; mb_index++) {
/* skip header */
quant = buf_ptr[3] & 0x0f;
buf_ptr += 4;
init_put_bits(&pb, mb_bit_buffer, 80);
mb_bit_count = 0;
mb = mb1;
block = block1;
for(j = 0;j < 6; j++) {
/* NOTE: size is not important here */
init_get_bits(&s->gb, buf_ptr, 14*8);
/* get the dc */
dc = get_bits(&s->gb, 9);
dc = (dc << (32 - 9)) >> (32 - 9);
dct_mode = get_bits1(&s->gb);
mb->dct_mode = dct_mode;
mb->scan_table = s->dv_zigzag[dct_mode];
class1 = get_bits(&s->gb, 2);
mb->shift_offset = (class1 == 3);
mb->shift_table = s->dv_idct_shift[dct_mode]
[quant + dv_quant_offset[class1]];
dc = dc << 2;
/* convert to unsigned because 128 is not added in the
standard IDCT */
dc += 1024;
block[0] = dc;
last_index = block_sizes[j];
buf_ptr += last_index >> 3;
mb->pos = 0;
mb->partial_bit_count = 0;
#ifdef VLC_DEBUG
printf("MB block: %d, %d ", mb_index, j);
#endif
dv_decode_ac(s, mb, block, last_index);
/* write the remaining bits in a new buffer only if the
block is finished */
bits_left = last_index - get_bits_count(&s->gb);
if (mb->eob_reached) {
mb->partial_bit_count = 0;
mb_bit_count += bits_left;
bit_copy(&pb, &s->gb, bits_left);
} else {
/* should be < 16 bits otherwise a codeword could have
been parsed */
mb->partial_bit_count = bits_left;
mb->partial_bit_buffer = get_bits(&s->gb, bits_left);
}
block += 64;
mb++;
}
flush_put_bits(&pb);
/* pass 2 : we can do it just after */
#ifdef VLC_DEBUG
printf("***pass 2 size=%d MB#=%d\n", mb_bit_count, mb_index);
#endif
block = block1;
mb = mb1;
init_get_bits(&s->gb, mb_bit_buffer, 80*8);
for(j = 0;j < 6; j++) {
if (!mb->eob_reached && get_bits_count(&s->gb) < mb_bit_count) {
dv_decode_ac(s, mb, block, mb_bit_count);
/* if still not finished, no need to parse other blocks */
if (!mb->eob_reached) {
/* we could not parse the current AC coefficient,
so we add the remaining bytes */
bits_left = mb_bit_count - get_bits_count(&s->gb);
if (bits_left > 0) {
mb->partial_bit_count += bits_left;
mb->partial_bit_buffer =
(mb->partial_bit_buffer << bits_left) |
get_bits(&s->gb, bits_left);
}
goto next_mb;
}
}
block += 64;
mb++;
}
/* all blocks are finished, so the extra bytes can be used at
the video segment level */
bits_left = mb_bit_count - get_bits_count(&s->gb);
vs_bit_count += bits_left;
bit_copy(&vs_pb, &s->gb, bits_left);
next_mb:
mb1 += 6;
block1 += 6 * 64;
}
/* we need a pass other the whole video segment */
flush_put_bits(&vs_pb);
#ifdef VLC_DEBUG
printf("***pass 3 size=%d\n", vs_bit_count);
#endif
block = &s->block[0][0];
mb = mb_data;
init_get_bits(&s->gb, vs_bit_buffer, 5 * 80*8);
for(mb_index = 0; mb_index < 5; mb_index++) {
for(j = 0;j < 6; j++) {
if (!mb->eob_reached) {
#ifdef VLC_DEBUG
printf("start %d:%d\n", mb_index, j);
#endif
dv_decode_ac(s, mb, block, vs_bit_count);
}
block += 64;
mb++;
}
}
/* compute idct and place blocks */
block = &s->block[0][0];
mb = mb_data;
for(mb_index = 0; mb_index < 5; mb_index++) {
v = *mb_pos_ptr++;
mb_x = v & 0xff;
mb_y = v >> 8;
y_ptr = s->picture.data[0] + (mb_y * s->picture.linesize[0] * 8) + (mb_x * 8);
if (s->sys->pix_fmt == PIX_FMT_YUV411P)
c_offset = (mb_y * s->picture.linesize[1] * 8) + ((mb_x >> 2) * 8);
else
c_offset = ((mb_y >> 1) * s->picture.linesize[1] * 8) + ((mb_x >> 1) * 8);
for(j = 0;j < 6; j++) {
idct_put = s->idct_put[mb->dct_mode];
if (j < 4) {
if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x < (704 / 8)) {
/* NOTE: at end of line, the macroblock is handled as 420 */
idct_put(y_ptr + (j * 8), s->picture.linesize[0], block);
} else {
idct_put(y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->picture.linesize[0]),
s->picture.linesize[0], block);
}
} else {
if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x >= (704 / 8)) {
uint64_t aligned_pixels[64/8];
uint8_t *pixels= (uint8_t*)aligned_pixels;
uint8_t *c_ptr, *c_ptr1, *ptr;
int y, linesize;
/* NOTE: at end of line, the macroblock is handled as 420 */
idct_put(pixels, 8, block);
linesize = s->picture.linesize[6 - j];
c_ptr = s->picture.data[6 - j] + c_offset;
ptr = pixels;
for(y = 0;y < 8; y++) {
/* convert to 411P */
c_ptr1 = c_ptr + 8*linesize;
c_ptr[0]= ptr[0]; c_ptr1[0]= ptr[4];
c_ptr[1]= ptr[1]; c_ptr1[1]= ptr[5];
c_ptr[2]= ptr[2]; c_ptr1[2]= ptr[6];
c_ptr[3]= ptr[3]; c_ptr1[3]= ptr[7];
c_ptr += linesize;
ptr += 8;
}
} else {
/* don't ask me why they inverted Cb and Cr ! */
idct_put(s->picture.data[6 - j] + c_offset,
s->picture.linesize[6 - j], block);
}
}
block += 64;
mb++;
}
}
}
/* Converts run and level (where level != 0) pair into vlc, returning bit size */
static inline int dv_rl2vlc(int run, int l, uint32_t* vlc)
{
int sign = l >> 8;
int level = (l ^ sign) - sign;
int size;
sign = (sign & 1);
if (run < 15 && level < 23 && dv_vlc_codes[run][level] != -1) {
*vlc = (dv_vlc_bits[dv_vlc_codes[run][level]] << 1) | sign;
size = dv_vlc_len[dv_vlc_codes[run][level]] + 1;
}
else {
if (level < 23) {
*vlc = (dv_vlc_bits[dv_vlc_codes[0][level]] << 1) | sign;
size = dv_vlc_len[dv_vlc_codes[0][level]] + 1;
} else {
*vlc = 0xfe00 | (level << 1) | sign;
size = 16;
}
switch(run) {
case 0:
break;
case 1:
case 2:
*vlc |= ((0x7ce | (run - 1)) << size);
size += 11;
break;
case 3:
case 4:
case 5:
case 6:
*vlc |= ((0xfac | (run - 3)) << size);
size += 12;
break;
default:
*vlc |= ((0x1f80 | (run - 1)) << size);
size += 13;
break;
}
}
return size;
}
typedef struct EncBlockInfo {
int qno;
int cno;
int dct_mode;
int block_size;
DCTELEM *mb;
PutBitContext pb;
const uint8_t* zigzag_scan;
uint8_t *dv_shift;
} EncBlockInfo;
static inline int dv_bits_left(EncBlockInfo* bi)
{
return (bi->block_size - get_bit_count(&bi->pb));
}
static inline void dv_encode_ac(EncBlockInfo* bi, PutBitContext* heap)
{
int i, level, size, run = 0;
uint32_t vlc;
PutBitContext* cpb = &bi->pb;
int bias = (bi->cno == 3);
for (i=1; i<64; i++) {
level = bi->mb[bi->zigzag_scan[i]] / (1<<(bi->dv_shift[i] + bias));
if (level != 0) {
size = dv_rl2vlc(run, level, &vlc);
put_vlc:
#ifdef VLC_DEBUG
printf(" %3d:%3d", run, level);
#endif
if (cpb == &bi->pb && size > dv_bits_left(bi)) {
size -= dv_bits_left(bi);
put_bits(cpb, dv_bits_left(bi), vlc >> size);
vlc = vlc & ((1<<size)-1);
cpb = heap;
}
put_bits(cpb, size, vlc);
run = 0;
} else
run++;
}
if (i == 64) {
size = 4; vlc = 6; /* End Of Block stamp */
goto put_vlc;
}
}
static inline void dv_redistr_bits(EncBlockInfo* bi, int count, uint8_t* extra_data, int extra_bits, PutBitContext* heap)
{
int i;
GetBitContext gb;
init_get_bits(&gb, extra_data, extra_bits);
for (i=0; i<count; i++) {
int bits_left = dv_bits_left(bi);
#ifdef VLC_DEBUG
if (bits_left)
printf("------------> inserting %d bytes in %d:%d\n", bits_left, i/6, i%6);
#endif
if (bits_left > extra_bits) {
bit_copy(&bi->pb, &gb, extra_bits);
extra_bits = 0;
break;
} else
bit_copy(&bi->pb, &gb, bits_left);
extra_bits -= bits_left;
bi++;
}
if (extra_bits > 0 && heap)
bit_copy(heap, &gb, extra_bits);
}
static inline void dv_set_class_number(EncBlockInfo* bi, int j)
{
int i, max_ac = 0;
for (i=1; i<64; i++) {
int ac = abs(bi->mb[ff_zigzag_direct[i]]) / 4;
if (max_ac < ac)
max_ac = ac;
}
if (max_ac < 12)
bi->cno = j;
else if (max_ac < 24)
bi->cno = j + 1;
else if (max_ac < 36)
bi->cno = j + 2;
else
bi->cno = j + 3;
if (bi->cno > 3)
bi->cno = 3;
}
#define SQ(a) ((a)*(a))
static int dv_score_lines(DCTELEM *s, int stride) {
int score=0;
int x, y;
for(y=0; y<4; y++) {
for(x=0; x<8; x+=4){
score+= SQ(s[x ] - s[x +stride]) + SQ(s[x+1] - s[x+1+stride])
+SQ(s[x+2] - s[x+2+stride]) + SQ(s[x+3] - s[x+3+stride]);
}
s+= stride;
}
return score;
}
/*
* This is a very rough initial implementaion. The performance is
* horrible and the weighting is missing. But it's missing from the
* decoding step also -- so at least we're on the same page with decoder ;-)
*/
static inline void dv_encode_video_segment(DVVideoDecodeContext *s,
uint8_t *dif,
const uint16_t *mb_pos_ptr)
{
int mb_index, i, j, v;
int mb_x, mb_y, c_offset, linesize;
uint8_t* y_ptr;
uint8_t* data;
int do_edge_wrap;
DCTELEM *block;
EncBlockInfo enc_blks[5*6];
EncBlockInfo* enc_blk;
int free_vs_bits;
int extra_bits;
PutBitContext extra_vs;
uint8_t extra_vs_data[5*6*128];
uint8_t extra_mb_data[6*128];
int QNO = 15;
/* Stage 1 -- doing DCT on 5 MBs */
block = &s->block[0][0];
enc_blk = &enc_blks[0];
for(mb_index = 0; mb_index < 5; mb_index++) {
v = *mb_pos_ptr++;
mb_x = v & 0xff;
mb_y = v >> 8;
y_ptr = s->picture.data[0] + (mb_y * s->picture.linesize[0] * 8) + (mb_x * 8);
c_offset = (s->sys->pix_fmt == PIX_FMT_YUV411P) ?
((mb_y * s->picture.linesize[1] * 8) + ((mb_x >> 2) * 8)) :
(((mb_y >> 1) * s->picture.linesize[1] * 8) + ((mb_x >> 1) * 8));
do_edge_wrap = 0;
for(j = 0;j < 6; j++) {
if (j < 4) { /* Four Y blocks */
/* NOTE: at end of line, the macroblock is handled as 420 */
if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x < (704 / 8)) {
data = y_ptr + (j * 8);
} else {
data = y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->picture.linesize[0]);
}
linesize = s->picture.linesize[0];
} else { /* Cr and Cb blocks */
/* don't ask Fabrice why they inverted Cb and Cr ! */
data = s->picture.data[6 - j] + c_offset;
linesize = s->picture.linesize[6 - j];
if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x >= (704 / 8))
do_edge_wrap = 1;
}
/* Everything is set up -- now just copy data -> DCT block */
if (do_edge_wrap) { /* Edge wrap copy: 4x16 -> 8x8 */
uint8_t* d;
DCTELEM *b = block;
for (i=0;i<8;i++) {
d = data + 8 * linesize;
b[0] = data[0]; b[1] = data[1]; b[2] = data[2]; b[3] = data[3];
b[4] = d[0]; b[5] = d[1]; b[6] = d[2]; b[7] = d[3];
data += linesize;
b += 8;
}
} else { /* Simple copy: 8x8 -> 8x8 */
s->get_pixels(block, data, linesize);
}
if (dv_score_lines(block, 8) + dv_score_lines(block+8*4, 8) - 100 >
dv_score_lines(block, 16) + dv_score_lines(block+8, 16)) {
enc_blk->dct_mode = 1;
enc_blk->zigzag_scan = ff_zigzag248_direct;
} else {
enc_blk->dct_mode = 0;
enc_blk->zigzag_scan = ff_zigzag_direct;
}
enc_blk->mb = block;
enc_blk->block_size = block_sizes[j];
s->fdct[enc_blk->dct_mode](block);
dv_set_class_number(enc_blk, j/4*(j%2));
block += 64;
enc_blk++;
}
}
/* Stage 2 -- encoding by trial-and-error */
encode_vs:
enc_blk = &enc_blks[0];
for (i=0; i<5; i++) {
uint8_t* p = dif + i*80 + 4;
for (j=0; j<6; j++) {
enc_blk->qno = QNO;
enc_blk->dv_shift = &(s->dv_dct_shift[0]
[QNO + dv_quant_offset[enc_blk->cno]][0]);
init_put_bits(&enc_blk->pb, p, block_sizes[j]/8);
enc_blk++;
p += block_sizes[j]/8;
}
}
init_put_bits(&extra_vs, extra_vs_data, sizeof(extra_vs_data));
free_vs_bits = 0;
enc_blk = &enc_blks[0];
for (i=0; i<5; i++) {
PutBitContext extra_mb;
EncBlockInfo* enc_blk2 = enc_blk;
int free_mb_bits = 0;
init_put_bits(&extra_mb, extra_mb_data, sizeof(extra_mb_data));
dif[i*80 + 3] = enc_blk->qno;
for (j=0; j<6; j++) {
uint16_t dc = ((enc_blk->mb[0] >> 3) - 1024) >> 2;
put_bits(&enc_blk->pb, 9, dc);
put_bits(&enc_blk->pb, 1, enc_blk->dct_mode);
put_bits(&enc_blk->pb, 2, enc_blk->cno);
#ifdef VLC_DEBUG
printf("[%d, %d]: ", i, j);
#endif
dv_encode_ac(enc_blk, &extra_mb);
#ifdef VLC_DEBUG
printf("\n");
#endif
free_mb_bits += dv_bits_left(enc_blk);
enc_blk++;
}
/* We can't flush extra_mb just yet -- since it'll round up bit number */
extra_bits = get_bit_count(&extra_mb);
if (free_mb_bits > extra_bits)
free_vs_bits += free_mb_bits - extra_bits;
if (extra_bits) { /* FIXME: speed up things when free_mb_bits == 0 */
flush_put_bits(&extra_mb);
dv_redistr_bits(enc_blk2, 6, extra_mb_data, extra_bits, &extra_vs);
}
}
/* We can't flush extra_mb just yet -- since it'll round up bit number */
extra_bits = get_bit_count(&extra_vs);
if (extra_bits > free_vs_bits && QNO) { /* FIXME: very crude trial-and-error */
QNO--;
goto encode_vs;
}
if (extra_bits) {
flush_put_bits(&extra_vs);
dv_redistr_bits(&enc_blks[0], 5*6, extra_vs_data, extra_bits, NULL);
}
for (i=0; i<6*5; i++) {
flush_put_bits(&enc_blks[i].pb);
#ifdef VLC_DEBUG
printf("[%d:%d] qno=%d cno=%d\n", i/6, i%6, enc_blks[i].qno, enc_blks[i].cno);
#endif
}
}
/* NOTE: exactly one frame must be given (120000 bytes for NTSC,
144000 bytes for PAL) */
static int dvvideo_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
uint8_t *buf, int buf_size)
{
DVVideoDecodeContext *s = avctx->priv_data;
int ds, vs;
const uint16_t *mb_pos_ptr;
s->sys = dv_frame_profile(buf);
if (!s->sys || buf_size < s->sys->frame_size)
return -1; /* NOTE: we only accept several full frames */
if(s->picture.data[0])
avctx->release_buffer(avctx, &s->picture);
s->picture.reference = 0;
avctx->pix_fmt = s->sys->pix_fmt;
avctx->width = s->sys->width;
avctx->height = s->sys->height;
if(avctx->get_buffer(avctx, &s->picture) < 0) {
fprintf(stderr, "get_buffer() failed\n");
return -1;
}
s->picture.interlaced_frame = 1;
s->picture.top_field_first = 0;
/* for each DIF segment */
mb_pos_ptr = s->sys->video_place;
for (ds = 0; ds < s->sys->difseg_size; ds++) {
buf += 6 * 80; /* skip DIF segment header */
for(vs = 0; vs < 27; vs++) {
if ((vs % 3) == 0)
buf += 80; /* skip audio block */
#ifdef VLC_DEBUG
printf("********************* %d, %d **********************\n", ds, vs);
#endif
dv_decode_video_segment(s, buf, mb_pos_ptr);
buf += 5 * 80;
mb_pos_ptr += 5;
}
}
emms_c();
/* return image */
*data_size = sizeof(AVFrame);
*(AVFrame*)data= s->picture;
return s->sys->frame_size;
}
static int dvvideo_encode_frame(AVCodecContext *c, uint8_t *buf, int buf_size,
void *data)
{
DVVideoDecodeContext *s = c->priv_data;
const uint16_t *mb_pos_ptr;
int ds, vs;
s->sys = dv_codec_profile(c);
if (!s->sys)
return -1;
c->pix_fmt = s->sys->pix_fmt;
s->picture = *((AVFrame *)data);
/* for each DIF segment */
mb_pos_ptr = s->sys->video_place;
for (ds = 0; ds < s->sys->difseg_size; ds++) {
buf += 6 * 80; /* skip DIF segment header */
for(vs = 0; vs < 27; vs++) {
if ((vs % 3) == 0)
buf += 80; /* skip audio block */
#ifdef VLC_DEBUG
printf("********************* %d, %d **********************\n", ds, vs);
#endif
dv_encode_video_segment(s, buf, mb_pos_ptr);
buf += 5 * 80;
mb_pos_ptr += 5;
}
}
emms_c();
return s->sys->frame_size;
}
static int dvvideo_end(AVCodecContext *avctx)
{
avcodec_default_free_buffers(avctx);
return 0;
}
AVCodec dvvideo_decoder = {
"dvvideo",
CODEC_TYPE_VIDEO,
CODEC_ID_DVVIDEO,
sizeof(DVVideoDecodeContext),
dvvideo_init,
dvvideo_encode_frame,
dvvideo_end,
dvvideo_decode_frame,
CODEC_CAP_DR1,
NULL
};