//very similar to MPEG-1
static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
{
int level, diff, i, j, run;
int component;
RLTable *rl = &ff_rl_mpeg1;
uint8_t * const scantable = a->scantable.permutated;
const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
const int qscale = a->qscale;
/* DC coefficient */
if (a->version == 2) {
block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
} else {
component = (n <= 3 ? 0 : n - 4 + 1);
diff = decode_dc(&a->gb, component);
if (diff >= 0xffff)
return AVERROR_INVALIDDATA;
a->last_dc[component] += diff;
block[0] = a->last_dc[component] << 3;
}
i = 0;
{
OPEN_READER(re, &a->gb);
/* now quantify & encode AC coefficients */
for (;;) {
UPDATE_CACHE(re, &a->gb);
GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
if (level == 127) {
break;
} else if (level != 0) {
i += run;
if (i > 63) {
av_log(a->avctx, AV_LOG_ERROR,
"ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
return AVERROR_INVALIDDATA;
}
j = scantable[i];
level = (level * qscale * quant_matrix[j]) >> 3;
level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
LAST_SKIP_BITS(re, &a->gb, 1);
} else {
/* escape */
run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
UPDATE_CACHE(re, &a->gb);
level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
i += run;
if (i > 63) {
av_log(a->avctx, AV_LOG_ERROR,
"ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
return AVERROR_INVALIDDATA;
}
j = scantable[i];
if (level < 0) {
level = -level;
level = (level * qscale * quant_matrix[j]) >> 3;
level = (level - 1) | 1;
level = -level;
} else {
static inline int decode_dct_block(const SHQContext *s, GetBitContext *gb, int last_dc[4], int component, uint8_t *dest, int linesize)
{
const int *quant_matrix = s->quant_matrix;
const uint8_t *scantable = s->intra_scantable.permutated;
LOCAL_ALIGNED_32(int16_t, block, [64]);
int dc_offset;
s->bdsp.clear_block(block);
dc_offset = decode_dc_le(gb, component);
last_dc[component] -= dc_offset; /* Note: Opposite of most codecs. */
block[scantable[0]] = last_dc[component]; /* quant_matrix[0] is always 16. */
/* Read AC coefficients. */
{
int i = 0;
OPEN_READER(re, gb);
for ( ;; ) {
int level, run;
UPDATE_CACHE_LE(re, gb);
GET_RL_VLC(level, run, re, gb, ff_rl_speedhq.rl_vlc[0],
TEX_VLC_BITS, 2, 0);
if (level == 127) {
break;
} else if (level) {
i += run;
if (i > MAX_INDEX)
return AVERROR_INVALIDDATA;
/* If next bit is 1, level = -level */
level = (level ^ SHOW_SBITS(re, gb, 1)) -
SHOW_SBITS(re, gb, 1);
LAST_SKIP_BITS(re, gb, 1);
} else {
/* Escape. */
#if MIN_CACHE_BITS < 6 + 6 + 12
#error MIN_CACHE_BITS is too small for the escape code, add UPDATE_CACHE
#endif
run = SHOW_UBITS(re, gb, 6) + 1;
SKIP_BITS(re, gb, 6);
level = SHOW_UBITS(re, gb, 12) - 2048;
LAST_SKIP_BITS(re, gb, 12);
i += run;
if (i > MAX_INDEX)
return AVERROR_INVALIDDATA;
}
block[scantable[i]] = (level * quant_matrix[i]) >> 4;
}
CLOSE_READER(re, gb);
}
s->idsp.idct_put(dest, linesize, block);
return 0;
}
static inline int decode_block_intra(MadContext *s, int16_t * block)
{
int level, i, j, run;
RLTable *rl = &ff_rl_mpeg1;
const uint8_t *scantable = s->scantable.permutated;
int16_t *quant_matrix = s->quant_matrix;
block[0] = (128 + get_sbits(&s->gb, 8)) * quant_matrix[0];
/* The RL decoder is derived from mpeg1_decode_block_intra;
Escaped level and run values a decoded differently */
i = 0;
{
OPEN_READER(re, &s->gb);
/* now quantify & encode AC coefficients */
for (;;) {
UPDATE_CACHE(re, &s->gb);
GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
if (level == 127) {
break;
} else if (level != 0) {
i += run;
if (i > 63) {
av_log(s->avctx, AV_LOG_ERROR,
"ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
j = scantable[i];
level = (level*quant_matrix[j]) >> 4;
level = (level-1)|1;
level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
LAST_SKIP_BITS(re, &s->gb, 1);
} else {
/* escape */
UPDATE_CACHE(re, &s->gb);
level = SHOW_SBITS(re, &s->gb, 10); SKIP_BITS(re, &s->gb, 10);
UPDATE_CACHE(re, &s->gb);
run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
i += run;
if (i > 63) {
av_log(s->avctx, AV_LOG_ERROR,
"ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
j = scantable[i];
if (level < 0) {
level = -level;
level = (level*quant_matrix[j]) >> 4;
level = (level-1)|1;
level = -level;
} else {
static inline void decode_block_intra(MadContext * t, DCTELEM * block)
{
MpegEncContext *s = &t->s;
int level, i, j, run;
RLTable *rl = &ff_rl_mpeg1;
const uint8_t *scantable = s->intra_scantable.permutated;
int16_t *quant_matrix = s->intra_matrix;
block[0] = (128 + get_sbits(&s->gb, 8)) * quant_matrix[0];
/* The RL decoder is derived from mpeg1_decode_block_intra;
Escaped level and run values a decoded differently */
i = 0;
{
OPEN_READER(re, &s->gb);
/* now quantify & encode AC coefficients */
for (;;) {
UPDATE_CACHE(re, &s->gb);
GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
if (level == 127) {
break;
} else if (level != 0) {
i += run;
j = scantable[i];
level = (level*quant_matrix[j]) >> 4;
level = (level-1)|1;
level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
LAST_SKIP_BITS(re, &s->gb, 1);
} else {
/* escape */
UPDATE_CACHE(re, &s->gb);
level = SHOW_SBITS(re, &s->gb, 10); SKIP_BITS(re, &s->gb, 10);
UPDATE_CACHE(re, &s->gb);
run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
i += run;
j = scantable[i];
if (level < 0) {
level = -level;
level = (level*quant_matrix[j]) >> 4;
level = (level-1)|1;
level = -level;
} else {
