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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00

simplified parsing - added MMX idct support

Originally committed as revision 1000 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Fabrice Bellard 2002-10-04 07:49:00 +00:00
parent 020fcc94e0
commit 7be166e4ea

View File

@ -36,8 +36,9 @@ typedef struct DVVideoDecodeContext {
int linesize[3];
DCTELEM block[5*6][64] __align8;
UINT8 dv_zigzag[2][64];
UINT8 idct_permutation[64];
/* XXX: move it to static storage ? */
UINT8 dv_shift[2][2][22][64];
UINT8 dv_shift[2][22][64];
void (*idct_put[2])(UINT8 *dest, int line_size, DCTELEM *block);
} DVVideoDecodeContext;
@ -49,24 +50,23 @@ static RL_VLC_ELEM *dv_rl_vlc[1];
static void dv_build_unquantize_tables(DVVideoDecodeContext *s)
{
int i, e, q;
int i, q, j;
/* NOTE: max left shift is 6 */
for(e = 0; e < 2; e++) {
for(q = 0; q < 22; q++) {
/* 88 unquant */
for(i = 1; i < 64; i++) {
/* 88 table */
s->dv_shift[0][e][q][i] =
dv_quant_shifts[q][dv_88_areas[i]] + e + 1;
}
/* 248 unquant */
for(i = 1; i < 64; i++) {
/* 248 table */
s->dv_shift[1][e][q][i] =
dv_quant_shifts[q][dv_248_areas[i]] + e + 1;
}
for(q = 0; q < 22; q++) {
/* 88 unquant */
for(i = 1; i < 64; i++) {
/* 88 table */
j = s->idct_permutation[i];
s->dv_shift[0][q][j] =
dv_quant_shifts[q][dv_88_areas[i]] + 1;
}
/* 248 unquant */
for(i = 1; i < 64; i++) {
/* 248 table */
s->dv_shift[1][q][i] =
dv_quant_shifts[q][dv_248_areas[i]] + 1;
}
}
}
@ -74,6 +74,7 @@ static void dv_build_unquantize_tables(DVVideoDecodeContext *s)
static int dvvideo_decode_init(AVCodecContext *avctx)
{
DVVideoDecodeContext *s = avctx->priv_data;
MpegEncContext s2;
static int done;
if (!done) {
@ -108,32 +109,46 @@ static int dvvideo_decode_init(AVCodecContext *avctx)
dv_rl_vlc[0][i].run = run;
}
}
/* ugly way to get the idct & scantable */
/* XXX: fix it */
memset(&s2, 0, sizeof(MpegEncContext));
s2.flags = avctx->flags;
s2.avctx = avctx;
// s2->out_format = FMT_MJPEG;
s2.width = 8;
s2.height = 8;
if (MPV_common_init(&s2) < 0)
return -1;
s->idct_put[0] = s2.idct_put;
memcpy(s->idct_permutation, s2.idct_permutation, 64);
memcpy(s->dv_zigzag[0], s2.intra_scantable.permutated, 64);
/* XXX: use MMX also for idct248 */
s->idct_put[1] = simple_idct248_put;
memcpy(s->dv_zigzag[1], dv_248_zigzag, 64);
MPV_common_end(&s2);
/* XXX: do it only for constant case */
dv_build_unquantize_tables(s);
{
/* XXX: fix that : use mmx when possible */
s->idct_put[0] = simple_idct_put;
s->idct_put[1] = simple_idct248_put;
memcpy(s->dv_zigzag[0], ff_zigzag_direct, 64);
memcpy(s->dv_zigzag[1], dv_248_zigzag, 64);
}
return 0;
}
//#define VLC_DEBUG
typedef struct MBInfo {
const UINT8 *shift_table[6];
const UINT8 *scan_table[6];
UINT8 pos[6]; /* position in block */
UINT8 eob_reached[6]; /* true if EOB has been reached */
UINT8 dct_mode[6];
UINT8 partial_bit_count[6];
UINT16 partial_bit_buffer[6];
UINT8 bit_buffer[80 + 4]; /* allow some slack */
int bits_left;
} MBInfo;
typedef struct BlockInfo {
const UINT8 *shift_table;
const UINT8 *scan_table;
UINT8 pos; /* position in block */
UINT8 eob_reached; /* true if EOB has been reached */
UINT8 dct_mode;
UINT8 partial_bit_count;
UINT16 partial_bit_buffer;
int shift_offset;
} BlockInfo;
/* block size in bits */
const static UINT16 block_sizes[6] = {
@ -146,23 +161,24 @@ const static UINT16 block_sizes[6] = {
/* decode ac coefs */
static void dv_decode_ac(DVVideoDecodeContext *s,
MBInfo *mb, INT16 *block, int j, int last_index)
BlockInfo *mb, INT16 *block, int last_index)
{
int last_re_index;
const UINT8 *scan_table = mb->scan_table[j];
const UINT8 *shift_table = mb->shift_table[j];
int pos = mb->pos[j];
int shift_offset = mb->shift_offset;
const UINT8 *scan_table = mb->scan_table;
const UINT8 *shift_table = mb->shift_table;
int pos = mb->pos;
int level, pos1, sign, run;
int partial_bit_count;
OPEN_READER(re, &s->gb);
#ifdef VLC_DEBUG
printf("start %d\n", j);
printf("start\n");
#endif
/* if we must parse a partial vlc, we do it here */
partial_bit_count = mb->partial_bit_count[j];
partial_bit_count = mb->partial_bit_count;
if (partial_bit_count > 0) {
UINT8 buf[4];
UINT32 v;
@ -175,12 +191,12 @@ static void dv_decode_ac(DVVideoDecodeContext *s,
#ifdef VLC_DEBUG
printf("show=%04x\n", SHOW_UBITS(re, &s->gb, 16));
#endif
v = (mb->partial_bit_buffer[j] << l) | SHOW_UBITS(re, &s->gb, l);
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[j] << l));
v, partial_bit_count, (mb->partial_bit_buffer << l));
#endif
/* try to read the codeword */
init_get_bits(&gb1, buf, 4);
@ -204,9 +220,9 @@ static void dv_decode_ac(DVVideoDecodeContext *s,
/* skip read bits */
last_re_index = 0; /* avoid warning */
re_index += l;
/* by redefinition, if we can read the vlc, all partial bits
/* 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[j] = 0;
mb->partial_bit_count = 0;
UPDATE_CACHE(re, &s->gb);
goto handle_vlc;
}
@ -230,11 +246,11 @@ static void dv_decode_ac(DVVideoDecodeContext *s,
cannot_read:
/* put position before read code */
re_index = last_re_index;
mb->eob_reached[j] = 0;
mb->eob_reached = 0;
break;
}
/* EOB */
mb->eob_reached[j] = 1;
mb->eob_reached = 1;
break;
} else if (level != 0) {
if ((re_index + 1) > last_index)
@ -248,7 +264,7 @@ static void dv_decode_ac(DVVideoDecodeContext *s,
goto read_error;
}
pos1 = scan_table[pos];
level = level << shift_table[pos1];
level = level << (shift_table[pos1] + shift_offset);
block[pos1] = level;
// printf("run=%d level=%d shift=%d\n", run, level, shift_table[pos1]);
} else {
@ -264,13 +280,13 @@ static void dv_decode_ac(DVVideoDecodeContext *s,
printf("error pos=%d\n", pos);
#endif
/* for errors, we consider the eob is reached */
mb->eob_reached[j] = 1;
mb->eob_reached = 1;
break;
}
}
}
CLOSE_READER(re, &s->gb);
mb->pos[j] = pos;
mb->pos = pos;
}
static inline void bit_copy(PutBitContext *pb, GetBitContext *gb, int bits_left)
@ -294,11 +310,13 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
DCTELEM *block, *block1;
int c_offset, bits_left;
UINT8 *y_ptr;
MBInfo mb_data[5], *mb;
BlockInfo mb_data[5 * 6], *mb, *mb1;
void (*idct_put)(UINT8 *dest, int line_size, DCTELEM *block);
UINT8 *buf_ptr;
PutBitContext pb, vs_pb;
UINT8 vs_bit_buffer[5 * 80 + 4];
UINT8 mb_bit_buffer[80 + 4]; /* allow some slack */
int mb_bit_count;
UINT8 vs_bit_buffer[5 * 80 + 4]; /* allow some slack */
int vs_bit_count;
memset(s->block, 0, sizeof(s->block));
@ -306,15 +324,16 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
/* pass 1 : read DC and AC coefficients in blocks */
buf_ptr = buf_ptr1;
block1 = &s->block[0][0];
mb = mb_data;
mb1 = mb_data;
init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80, NULL, NULL);
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, NULL, NULL);
mb->bits_left = 0;
init_put_bits(&pb, mb_bit_buffer, 80, NULL, NULL);
mb_bit_count = 0;
mb = mb1;
block = block1;
for(j = 0;j < 6; j++) {
/* NOTE: size is not important here */
@ -324,10 +343,11 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
dc = get_bits(&s->gb, 9);
dc = (dc << (32 - 9)) >> (32 - 9);
dct_mode = get_bits1(&s->gb);
mb->dct_mode[j] = dct_mode;
mb->scan_table[j] = s->dv_zigzag[dct_mode];
mb->dct_mode = dct_mode;
mb->scan_table = s->dv_zigzag[dct_mode];
class1 = get_bits(&s->gb, 2);
mb->shift_table[j] = s->dv_shift[dct_mode][class1 == 3]
mb->shift_offset = (class1 == 3);
mb->shift_table = s->dv_shift[dct_mode]
[quant + dv_quant_offset[class1]];
dc = dc << 2;
/* convert to unsigned because 128 is not added in the
@ -336,61 +356,64 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
block[0] = dc;
last_index = block_sizes[j];
buf_ptr += last_index >> 3;
mb->pos[j] = 0;
mb->partial_bit_count[j] = 0;
mb->pos = 0;
mb->partial_bit_count = 0;
dv_decode_ac(s, mb, block, j, last_index);
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 - s->gb.index;
if (mb->eob_reached[j]) {
mb->partial_bit_count[j] = 0;
mb->bits_left += bits_left;
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[j] = bits_left;
mb->partial_bit_buffer[j] = get_bits(&s->gb, bits_left);
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\n", mb->bits_left);
printf("***pass 2 size=%d\n", mb_bit_count);
#endif
block = block1;
init_get_bits(&s->gb, mb->bit_buffer, 80);
mb = mb1;
init_get_bits(&s->gb, mb_bit_buffer, 80);
for(j = 0;j < 6; j++) {
if (!mb->eob_reached[j] && s->gb.index < mb->bits_left) {
dv_decode_ac(s, mb, block, j, mb->bits_left);
if (!mb->eob_reached && s->gb.index < 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[j]) {
if (!mb->eob_reached) {
/* we could not parse the current AC coefficient,
so we add the remaining bytes */
bits_left = mb->bits_left - s->gb.index;
bits_left = mb_bit_count - s->gb.index;
if (bits_left > 0) {
mb->partial_bit_count[j] += bits_left;
mb->partial_bit_buffer[j] =
(mb->partial_bit_buffer[j] << bits_left) |
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->bits_left - s->gb.index;
bits_left = mb_bit_count - s->gb.index;
vs_bit_count += bits_left;
bit_copy(&vs_pb, &s->gb, bits_left);
next_mb:
mb++;
mb1 += 6;
block1 += 6 * 64;
}
@ -405,15 +428,15 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
init_get_bits(&s->gb, vs_bit_buffer, 5 * 80);
for(mb_index = 0; mb_index < 5; mb_index++) {
for(j = 0;j < 6; j++) {
if (!mb->eob_reached[j]) {
if (!mb->eob_reached) {
#ifdef VLC_DEBUG
printf("start %d:%d\n", mb_index, j);
#endif
dv_decode_ac(s, mb, block, j, vs_bit_count);
dv_decode_ac(s, mb, block, vs_bit_count);
}
block += 64;
mb++;
}
mb++;
}
/* compute idct and place blocks */
@ -429,7 +452,7 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
else
c_offset = ((mb_y >> 1) * s->linesize[1] * 8) + ((mb_x >> 1) * 8);
for(j = 0;j < 6; j++) {
idct_put = s->idct_put[mb->dct_mode[j]];
idct_put = s->idct_put[mb->dct_mode];
if (j < 4) {
if (s->sampling_411) {
idct_put(y_ptr + (j * 8), s->linesize[0], block);
@ -443,8 +466,8 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
s->linesize[6 - j], block);
}
block += 64;
mb++;
}
mb++;
}
}