[FFmpeg-devel] [PATCH v7 3/3] avcodec/jpeg2000dec: Fix HT decoding
Osamu Watanabe
owatanab at es.takushoku-u.ac.jp
Sun Aug 4 08:27:06 EEST 2024
This commit fixes wrong treatment of MAGBP value in Ccap15 and bugs in HT block decoding.
Signed-off-by: Osamu Watanabe <owatanab at es.takushoku-u.ac.jp>
---
libavcodec/jpeg2000dec.c | 11 +--
libavcodec/jpeg2000htdec.c | 136 ++++++++++++++++++++++---------------
libavcodec/jpeg2000htdec.h | 2 +-
3 files changed, 89 insertions(+), 60 deletions(-)
diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index c8759b6d51..fe6b542110 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -391,6 +391,9 @@ static int get_siz(Jpeg2000DecoderContext *s)
} else if (ncomponents == 1 && s->precision == 8) {
s->avctx->pix_fmt = AV_PIX_FMT_GRAY8;
i = 0;
+ } else if (ncomponents == 1 && s->precision == 12) {
+ s->avctx->pix_fmt = AV_PIX_FMT_GRAY16LE;
+ i = 0;
}
}
@@ -2204,7 +2207,7 @@ static inline int tile_codeblocks(const Jpeg2000DecoderContext *s, Jpeg2000Tile
Jpeg2000Band *band = rlevel->band + bandno;
int cblkno = 0, bandpos;
/* See Rec. ITU-T T.800, Equation E-2 */
- int magp = quantsty->expn[subbandno] + quantsty->nguardbits - 1;
+ int M_b = quantsty->expn[subbandno] + quantsty->nguardbits - 1;
bandpos = bandno + (reslevelno > 0);
@@ -2212,8 +2215,8 @@ static inline int tile_codeblocks(const Jpeg2000DecoderContext *s, Jpeg2000Tile
band->coord[1][0] == band->coord[1][1])
continue;
- if ((codsty->cblk_style & JPEG2000_CTSY_HTJ2K_F) && magp >= 31) {
- avpriv_request_sample(s->avctx, "JPEG2000_CTSY_HTJ2K_F and magp >= 31");
+ if ((codsty->cblk_style & JPEG2000_CTSY_HTJ2K_F) && M_b >= 31) {
+ avpriv_request_sample(s->avctx, "JPEG2000_CTSY_HTJ2K_F and M_b >= 31");
return AVERROR_PATCHWELCOME;
}
@@ -2234,7 +2237,7 @@ static inline int tile_codeblocks(const Jpeg2000DecoderContext *s, Jpeg2000Tile
ret = ff_jpeg2000_decode_htj2k(s, codsty, &t1, cblk,
cblk->coord[0][1] - cblk->coord[0][0],
cblk->coord[1][1] - cblk->coord[1][0],
- magp, comp->roi_shift);
+ M_b, comp->roi_shift);
else
ret = decode_cblk(s, codsty, &t1, cblk,
cblk->coord[0][1] - cblk->coord[0][0],
diff --git a/libavcodec/jpeg2000htdec.c b/libavcodec/jpeg2000htdec.c
index 9b473e11d3..0296792a6a 100644
--- a/libavcodec/jpeg2000htdec.c
+++ b/libavcodec/jpeg2000htdec.c
@@ -122,7 +122,7 @@ static void jpeg2000_init_mel(StateVars *s, uint32_t Pcup)
static void jpeg2000_init_mag_ref(StateVars *s, uint32_t Lref)
{
- s->pos = Lref - 2;
+ s->pos = Lref - 1;
s->bits = 0;
s->last = 0xFF;
s->tmp = 0;
@@ -145,9 +145,10 @@ static void jpeg2000_init_mel_decoder(MelDecoderState *mel_state)
static int jpeg2000_bitbuf_refill_backwards(StateVars *buffer, const uint8_t *array)
{
uint64_t tmp = 0;
- int32_t position = buffer->pos - 4;
uint32_t new_bits = 32;
+ buffer->last = array[buffer->pos + 1];
+
if (buffer->bits_left >= 32)
return 0; // enough data, no need to pull in more bits
@@ -157,9 +158,24 @@ static int jpeg2000_bitbuf_refill_backwards(StateVars *buffer, const uint8_t *ar
* the bottom most bits.
*/
- for(int i = FFMAX(0, position + 1); i <= buffer->pos + 1; i++)
- tmp = 256*tmp + array[i];
-
+ if (buffer->pos >= 3) { // Common case; we have at least 4 bytes available
+ tmp = array[buffer->pos - 3];
+ tmp = (tmp << 8) | array[buffer->pos - 2];
+ tmp = (tmp << 8) | array[buffer->pos - 1];
+ tmp = (tmp << 8) | array[buffer->pos];
+ tmp = (tmp << 8) | buffer->last; // For stuffing bit detection
+ buffer->pos -= 4;
+ } else {
+ if (buffer->pos >= 2)
+ tmp = array[buffer->pos - 2];
+ if (buffer->pos >= 1)
+ tmp = (tmp << 8) | array[buffer->pos - 1];
+ if (buffer->pos >= 0)
+ tmp = (tmp << 8) | array[buffer->pos];
+ buffer->pos = 0;
+ tmp = (tmp << 8) | buffer->last; // For stuffing bit detection
+ }
+ // Now remove any stuffing bits, shifting things down as we go
if ((tmp & 0x7FFF000000) > 0x7F8F000000) {
tmp &= 0x7FFFFFFFFF;
new_bits--;
@@ -176,13 +192,11 @@ static int jpeg2000_bitbuf_refill_backwards(StateVars *buffer, const uint8_t *ar
tmp = (tmp & 0x0000007FFF) + ((tmp & 0xFFFFFF0000) >> 1);
new_bits--;
}
-
- tmp >>= 8; // Remove temporary byte loaded
+ tmp >>= 8; // Shifts away the extra byte we imported
/* Add bits to the MSB of the bit buffer */
buffer->bit_buf |= tmp << buffer->bits_left;
buffer->bits_left += new_bits;
- buffer->pos = FFMAX(0, position);
return 0;
}
@@ -406,6 +420,7 @@ static void recover_mag_sgn(StateVars *mag_sgn, uint8_t pos, uint16_t q, int32_t
E[n] = 32 - ff_clz(v[pos][i] | 1);
mu_n[n] = (v[pos][i] >> 1) + 1;
mu_n[n] <<= pLSB;
+ mu_n[n] |= (1 << (pLSB - 1)); // Add 0.5 (reconstruction parameter = 1/2)
mu_n[n] |= ((uint32_t) (v[pos][i] & 1)) << 31; // sign bit.
}
}
@@ -414,7 +429,7 @@ static void recover_mag_sgn(StateVars *mag_sgn, uint8_t pos, uint16_t q, int32_t
static int jpeg2000_import_bit(StateVars *stream, const uint8_t *array, uint32_t length)
{
int cond = stream->pos < length;
- int pos = FFMIN(stream->pos, length);
+ int pos = FFMIN(stream->pos, length - 1);
if (stream->bits == 0) {
stream->bits = (stream->tmp == 0xFF) ? 7 : 8;
stream->pos += cond;
@@ -426,14 +441,22 @@ static int jpeg2000_import_bit(StateVars *stream, const uint8_t *array, uint32_t
static int jpeg2000_peek_bit(StateVars *stream, const uint8_t *array, uint32_t length)
{
+ uint8_t bit;
+
if (stream->bits == 0) {
- int cond = stream->pos < length;
- int pos = FFMIN(stream->pos, length);
- stream->bits = (stream->tmp == 0xFF) ? 7 : 8;
- stream->pos += cond;
- stream->tmp = cond ? array[pos] : 0xFF;
+ stream->bits = (stream->last == 0xFF) ? 7 : 8;
+ if (stream->pos < length) {
+ stream->tmp = array[stream->pos];
+ stream->pos++;
+ } else {
+ stream->tmp = 0;
+ }
+ stream->last = stream->tmp;
}
- return (stream->tmp >> stream->bits) & 1;
+ bit = stream->tmp & 1;
+ stream->tmp >>= 1;
+ stream->bits--;
+ return bit;
}
static int jpeg2000_decode_mel_sym(MelDecoderState *mel_state,
@@ -994,39 +1017,18 @@ static void jpeg2000_calc_mbr(uint8_t *mbr, const uint16_t i, const uint16_t j,
const uint32_t mbr_info, uint8_t causal_cond,
uint8_t *block_states, int stride)
{
- int local_mbr = 0;
-
- local_mbr |= jpeg2000_get_state(i - 1, j - 1, stride, HT_SHIFT_SIGMA, block_states);
- local_mbr |= jpeg2000_get_state(i - 1, j + 0, stride, HT_SHIFT_SIGMA, block_states);
- local_mbr |= jpeg2000_get_state(i - 1, j + 1, stride, HT_SHIFT_SIGMA, block_states);
-
- local_mbr |= jpeg2000_get_state(i + 0, j - 1, stride, HT_SHIFT_SIGMA, block_states);
- local_mbr |= jpeg2000_get_state(i + 0, j + 1, stride, HT_SHIFT_SIGMA, block_states);
-
- local_mbr |= jpeg2000_get_state(i + 1, j - 1, stride, HT_SHIFT_SIGMA, block_states) * causal_cond;
- local_mbr |= jpeg2000_get_state(i + 1, j + 0, stride, HT_SHIFT_SIGMA, block_states) * causal_cond;
- local_mbr |= jpeg2000_get_state(i + 1, j + 1, stride, HT_SHIFT_SIGMA, block_states) * causal_cond;
-
- local_mbr |= jpeg2000_get_state(i - 1, j - 1, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i - 1, j - 1, stride, HT_SHIFT_SCAN, block_states);
- local_mbr |= jpeg2000_get_state(i - 1, j + 0, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i - 1, j - 1, stride, HT_SHIFT_SCAN, block_states);
- local_mbr |= jpeg2000_get_state(i - 1, j + 1, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i - 1, j + 1, stride, HT_SHIFT_SCAN, block_states);
-
- local_mbr |= jpeg2000_get_state(i + 0, j - 1, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i + 0, j - 1, stride, HT_SHIFT_SCAN, block_states);
- local_mbr |= jpeg2000_get_state(i + 0, j + 1, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i + 0, j + 1, stride, HT_SHIFT_SCAN, block_states);
-
- local_mbr |= jpeg2000_get_state(i + 1, j - 1, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i + 1, j - 1, stride, HT_SHIFT_SCAN, block_states) * causal_cond;
- local_mbr |= jpeg2000_get_state(i + 1, j + 0, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i + 1, j + 0, stride, HT_SHIFT_SCAN, block_states) * causal_cond;
- local_mbr |= jpeg2000_get_state(i + 1, j + 1, stride, HT_SHIFT_REF, block_states) *
- jpeg2000_get_state(i + 1, j + 1, stride, HT_SHIFT_SCAN, block_states) * causal_cond;
-
- *mbr |= local_mbr;
+ uint8_t *state_p0 = block_states + i * stride + j;
+ uint8_t *state_p1 = block_states + (i + 1) * stride + j;
+ uint8_t *state_p2 = block_states + (i + 2) * stride + j;
+
+ uint8_t mbr0 = state_p0[0] | state_p0[1] | state_p0[2];
+ uint8_t mbr1 = state_p1[0] | state_p1[2];
+ uint8_t mbr2 = state_p2[0] | state_p2[1] | state_p2[2];
+ *mbr = mbr0 | mbr1 | (mbr2 & causal_cond);
+ *mbr |= (mbr0 >> HT_SHIFT_REF) & (mbr0 >> HT_SHIFT_SCAN);
+ *mbr |= (mbr1 >> HT_SHIFT_REF) & (mbr1 >> HT_SHIFT_SCAN);
+ *mbr |= (mbr2 >> HT_SHIFT_REF) & (mbr2 >> HT_SHIFT_SCAN) & causal_cond;
+ *mbr &= 1;
}
static void jpeg2000_process_stripes_block(StateVars *sig_prop, int i_s, int j_s,
@@ -1060,6 +1062,18 @@ static void jpeg2000_process_stripes_block(StateVars *sig_prop, int i_s, int j_s
jpeg2000_modify_state(i, j, stride, modify_state, block_states);
}
}
+ // decode sign
+ for (int j = j_s; j < j_s + width; j++) {
+ for (int i = i_s; i < i_s + height; i++) {
+ uint8_t bit;
+ int32_t *sp = &sample_buf[j + (i * (stride))];
+ uint8_t *state_p = block_states + (i + 1) * stride + (j + 1);
+ if ((state_p[0] >> HT_SHIFT_REF) & 1) {
+ bit = jpeg2000_peek_bit(sig_prop, magref_segment, magref_length);
+ *sp |= (int32_t)bit << 31;
+ }
+ }
+ }
}
/**
@@ -1130,7 +1144,8 @@ jpeg2000_decode_magref_segment( uint16_t width, uint16_t block_height, const int
uint16_t height = 4;
uint16_t i_start = 0;
int32_t *sp;
-
+ int32_t bit;
+ int32_t tmp;
jpeg2000_init_mag_ref(&mag_ref, magref_length);
for (int n1 = 0; n1 < num_v_stripe; n1++) {
@@ -1141,9 +1156,13 @@ jpeg2000_decode_magref_segment( uint16_t width, uint16_t block_height, const int
* Rec. ITU-T T.814, Figure 7.
*/
sp = &sample_buf[j + i * stride];
- if (jpeg2000_get_state(i, j, width, HT_SHIFT_SIGMA, block_states) != 0) {
- jpeg2000_modify_state(i, j, width, 1 << HT_SHIFT_REF_IND, block_states);
- *sp |= jpeg2000_import_magref_bit(&mag_ref, magref_segment, magref_length) << pLSB;
+ if (jpeg2000_get_state(i, j, stride, HT_SHIFT_SIGMA, block_states) != 0) {
+ jpeg2000_modify_state(i, j, stride, 1 << HT_SHIFT_REF_IND, block_states);
+ bit = jpeg2000_import_magref_bit(&mag_ref, magref_segment, magref_length);
+ tmp = 0xFFFFFFFE | (uint32_t)bit;
+ tmp <<= pLSB;
+ sp[0] &= tmp;
+ sp[0] |= 1 << (pLSB - 1); // Add 0.5 (reconstruction parameter = 1/2)
}
}
}
@@ -1153,9 +1172,13 @@ jpeg2000_decode_magref_segment( uint16_t width, uint16_t block_height, const int
for (int j = 0; j < width; j++) {
for (int i = i_start; i < i_start + height; i++) {
sp = &sample_buf[j + i * stride];
- if (jpeg2000_get_state(i, j, width, HT_SHIFT_SIGMA, block_states) != 0) {
- jpeg2000_modify_state(i, j, width, 1 << HT_SHIFT_REF_IND, block_states);
- *sp |= jpeg2000_import_magref_bit(&mag_ref, magref_segment, magref_length) << pLSB;
+ if (jpeg2000_get_state(i, j, stride, HT_SHIFT_SIGMA, block_states) != 0) {
+ jpeg2000_modify_state(i, j, stride, 1 << HT_SHIFT_REF_IND, block_states);
+ bit = jpeg2000_import_magref_bit(&mag_ref, magref_segment, magref_length);
+ tmp = 0xFFFFFFFE | (uint32_t)bit;
+ tmp <<= pLSB;
+ sp[0] &= tmp;
+ sp[0] |= 1 << (pLSB - 1); // Add 0.5 (reconstruction parameter = 1/2)
}
}
}
@@ -1233,6 +1256,9 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
}
Dcup = cblk->data;
Dref = cblk->data + Lcup; // Dref comes after the refinement segment
+
+ cblk->data[cblk->length] = 0xFF; // an extra byte for refinement segment (buffer->last)
+
S_blk = p0 + cblk->zbp;
cblk->zbp = S_blk - 1;
pLSB = 30 - S_blk;
diff --git a/libavcodec/jpeg2000htdec.h b/libavcodec/jpeg2000htdec.h
index 572d095c92..8d6919a0de 100644
--- a/libavcodec/jpeg2000htdec.h
+++ b/libavcodec/jpeg2000htdec.h
@@ -29,6 +29,6 @@
int ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *codsty,
Jpeg2000T1Context *t1, Jpeg2000Cblk *cblk, int width,
- int height, int magp, uint8_t roi_shift);
+ int height, int M_b, uint8_t roi_shift);
#endif /* AVCODEC_JPEG2000HTDEC_H */
--
2.34.1
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