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Merge commit '249827f736db4c94dfcb24a3883aa4c04f9b119b'

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* commit '249827f736db4c94dfcb24a3883aa4c04f9b119b':
  mpeg12dec: Refactor mpeg1_decode_block_intra()

Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
This commit is contained in:
Derek Buitenhuis 2016-02-16 19:05:26 +00:00
commit 8e2105297d
1 changed files with 18 additions and 11 deletions
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29
libavcodec/mpeg12dec.c
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@ -135,26 +135,27 @@ static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
} while (0) } while (0)
static inline int mpeg1_decode_block_intra(MpegEncContext *s, static inline int mpeg1_decode_block_intra(MpegEncContext *s,
int16_t *block, int n) int16_t *block, int index)
{ {
int level, dc, diff, i, j, run; int dc, diff, i = 0, component;
int component; RLTable *rl = &ff_rl_mpeg1;
RLTable *rl = &ff_rl_mpeg1;
uint8_t *const scantable = s->intra_scantable.permutated; uint8_t *const scantable = s->intra_scantable.permutated;
const uint16_t *quant_matrix = s->intra_matrix; const uint16_t *quant_matrix = s->intra_matrix;
const int qscale = s->qscale; const int qscale = s->qscale;
/* DC coefficient */ /* DC coefficient */
component = (n <= 3 ? 0 : n - 4 + 1); component = index <= 3 ? 0 : index - 4 + 1;
diff = decode_dc(&s->gb, component); diff = decode_dc(&s->gb, component);
if (diff >= 0xffff) if (diff >= 0xffff)
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
dc = s->last_dc[component]; dc = s->last_dc[component];
dc += diff; dc += diff;
s->last_dc[component] = dc; s->last_dc[component] = dc;
block[0] = dc * quant_matrix[0]; block[0] = dc * quant_matrix[0];
ff_tlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
i = 0;
{ {
OPEN_READER(re, &s->gb); OPEN_READER(re, &s->gb);
UPDATE_CACHE(re, &s->gb); UPDATE_CACHE(re, &s->gb);
@ -162,7 +163,9 @@ static inline int mpeg1_decode_block_intra(MpegEncContext *s,
goto end; goto end;
/* now quantify & encode AC coefficients */ /* now quantify & encode AC coefficients */
for (;;) { while (1) {
int level, run, j;
GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
TEX_VLC_BITS, 2, 0); TEX_VLC_BITS, 2, 0);
@ -170,6 +173,7 @@ static inline int mpeg1_decode_block_intra(MpegEncContext *s,
i += run; i += run;
if (i > MAX_INDEX) if (i > MAX_INDEX)
break; break;
j = scantable[i]; j = scantable[i];
level = (level * qscale * quant_matrix[j]) >> 4; level = (level * qscale * quant_matrix[j]) >> 4;
level = (level - 1) | 1; level = (level - 1) | 1;
@ -183,6 +187,7 @@ static inline int mpeg1_decode_block_intra(MpegEncContext *s,
UPDATE_CACHE(re, &s->gb); UPDATE_CACHE(re, &s->gb);
level = SHOW_SBITS(re, &s->gb, 8); level = SHOW_SBITS(re, &s->gb, 8);
SKIP_BITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
if (level == -128) { if (level == -128) {
level = SHOW_UBITS(re, &s->gb, 8) - 256; level = SHOW_UBITS(re, &s->gb, 8) - 256;
SKIP_BITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
@ -190,9 +195,11 @@ static inline int mpeg1_decode_block_intra(MpegEncContext *s,
level = SHOW_UBITS(re, &s->gb, 8); level = SHOW_UBITS(re, &s->gb, 8);
SKIP_BITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
} }
i += run; i += run;
if (i > MAX_INDEX) if (i > MAX_INDEX)
break; break;
j = scantable[i]; j = scantable[i];
if (level < 0) { if (level < 0) {
level = -level; level = -level;
@ -218,13 +225,13 @@ end:
check_scantable_index(s, i); check_scantable_index(s, i);
s->block_last_index[n] = i; s->block_last_index[index] = i;
return 0; return 0;
} }
int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n) int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int index)
{ {
return mpeg1_decode_block_intra(s, block, n); return mpeg1_decode_block_intra(s, block, index);
} }
static inline int mpeg1_decode_block_inter(MpegEncContext *s, static inline int mpeg1_decode_block_inter(MpegEncContext *s,