[FFmpeg-devel] [PATCH v6 2/3] avcodec/jpeg2000dec: Add support for placeholder passes
Osamu Watanabe
owatanab at es.takushoku-u.ac.jp
Thu Aug 1 05:37:25 EEST 2024
This commit adds support for placeholder pass parsing.
Signed-off-by: Osamu Watanabe <owatanab at es.takushoku-u.ac.jp>
---
libavcodec/jpeg2000.h | 2 +
libavcodec/jpeg2000dec.c | 352 +++++++++++++++++++++++++++++--------
libavcodec/jpeg2000htdec.c | 90 +++++-----
3 files changed, 326 insertions(+), 118 deletions(-)
diff --git a/libavcodec/jpeg2000.h b/libavcodec/jpeg2000.h
index 4bdc38df7c..93221d90ca 100644
--- a/libavcodec/jpeg2000.h
+++ b/libavcodec/jpeg2000.h
@@ -200,6 +200,8 @@ typedef struct Jpeg2000Cblk {
/* specific to HT code-blocks */
int zbp;
int pass_lengths[2];
+ uint8_t modes; // copy of SPcod/SPcoc field to parse HT-MIXED mode
+ uint8_t ht_plhd; // are we looking for HT placeholder passes?
} Jpeg2000Cblk; // code block
typedef struct Jpeg2000Prec {
diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index a1f82389fa..00ff9bea6f 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -54,6 +54,15 @@
#define HAD_COC 0x01
#define HAD_QCC 0x02
+// Values of flag for placeholder passes
+enum HT_PLHD_STATUS {
+ HT_PLHD_OFF,
+ HT_PLHD_ON
+};
+
+#define HT_MIXED 0x80 // bit 7 of SPcod/SPcoc
+
+
/* get_bits functions for JPEG2000 packet bitstream
* It is a get_bit function with a bit-stuffing routine. If the value of the
* byte is 0xFF, the next byte includes an extra zero bit stuffed into the MSB.
@@ -1160,100 +1169,293 @@ static int jpeg2000_decode_packet(Jpeg2000DecoderContext *s, Jpeg2000Tile *tile,
int incl, newpasses, llen;
void *tmp;
- if (cblk->npasses)
- incl = get_bits(s, 1);
- else
+ if (!cblk->incl) {
+ incl = 0;
+ cblk->modes = codsty->cblk_style;
+ if (cblk->modes >= JPEG2000_CTSY_HTJ2K_F)
+ cblk->ht_plhd = HT_PLHD_ON;
+ if (layno > 0)
+ incl = tag_tree_decode(s, prec->cblkincl + cblkno, 0 + 1) == 0;
incl = tag_tree_decode(s, prec->cblkincl + cblkno, layno + 1) == layno;
- if (!incl)
- continue;
- else if (incl < 0)
- return incl;
-
- if (!cblk->npasses) {
- int zbp = tag_tree_decode(s, prec->zerobits + cblkno, 100);
- int v = expn[bandno] + numgbits - 1 - zbp;
- if (v < 0 || v > 30) {
- av_log(s->avctx, AV_LOG_ERROR,
- "nonzerobits %d invalid or unsupported\n", v);
- return AVERROR_INVALIDDATA;
+ if (incl) {
+ int zbp = tag_tree_decode(s, prec->zerobits + cblkno, 100);
+ int v = expn[bandno] + numgbits - 1 - (zbp - tile->comp->roi_shift);
+ if (v < 0 || v > 30) {
+ av_log(s->avctx, AV_LOG_ERROR,
+ "nonzerobits %d invalid or unsupported\n", v);
+ return AVERROR_INVALIDDATA;
+ }
+ cblk->incl = 1;
+ cblk->nonzerobits = v;
+ cblk->zbp = zbp;
+ cblk->lblock = 3;
}
- cblk->zbp = zbp;
- cblk->nonzerobits = v;
- }
- if ((newpasses = getnpasses(s)) < 0)
- return newpasses;
- av_assert2(newpasses > 0);
- if (cblk->npasses + newpasses >= JPEG2000_MAX_PASSES) {
- avpriv_request_sample(s->avctx, "Too many passes");
- return AVERROR_PATCHWELCOME;
- }
- if ((llen = getlblockinc(s)) < 0)
- return llen;
- if (cblk->lblock + llen + av_log2(newpasses) > 16) {
- avpriv_request_sample(s->avctx,
- "Block with length beyond 16 bits");
- return AVERROR_PATCHWELCOME;
+ } else {
+ incl = get_bits(s, 1);
}
- cblk->lblock += llen;
-
- cblk->nb_lengthinc = 0;
- cblk->nb_terminationsinc = 0;
- av_free(cblk->lengthinc);
- cblk->lengthinc = av_calloc(newpasses, sizeof(*cblk->lengthinc));
- if (!cblk->lengthinc)
- return AVERROR(ENOMEM);
- tmp = av_realloc_array(cblk->data_start, cblk->nb_terminations + newpasses + 1, sizeof(*cblk->data_start));
- if (!tmp)
- return AVERROR(ENOMEM);
- cblk->data_start = tmp;
- do {
- int newpasses1 = 0;
+ if (incl) {
+ uint8_t bypass_term_threshold = 0;
+ uint8_t bits_to_read = 0;
+ uint32_t segment_bytes = 0;
+ int32_t segment_passes = 0;
+ uint8_t next_segment_passes = 0;
+ int32_t href_passes, pass_bound;
+ uint32_t tmp_length = 0;
+ int32_t newpasses_copy, npasses_copy;
+
+ if ((newpasses = getnpasses(s)) <= 0)
+ return newpasses;
+ if (cblk->npasses + newpasses >= JPEG2000_MAX_PASSES) {
+ avpriv_request_sample(s->avctx, "Too many passes");
+ return AVERROR_PATCHWELCOME;
+ }
+ if ((llen = getlblockinc(s)) < 0)
+ return llen;
+ if (cblk->lblock + llen + av_log2(newpasses) > 16) {
+ avpriv_request_sample(s->avctx,
+ "Block with length beyond 16 bits");
+ return AVERROR_PATCHWELCOME;
+ }
+ cblk->nb_lengthinc = 0;
+ cblk->nb_terminationsinc = 0;
+ av_free(cblk->lengthinc);
+ cblk->lengthinc = av_calloc(newpasses, sizeof(*cblk->lengthinc));
+ if (!cblk->lengthinc)
+ return AVERROR(ENOMEM);
+ tmp = av_realloc_array(cblk->data_start, cblk->nb_terminations + newpasses + 1,
+ sizeof(*cblk->data_start));
+ if (!tmp)
+ return AVERROR(ENOMEM);
+ cblk->data_start = tmp;
+ cblk->lblock += llen;
+
+ // Count number of necessary terminations for non HT code block
+ newpasses_copy = newpasses;
+ npasses_copy = cblk->npasses;
+ if (!(cblk->modes & JPEG2000_CTSY_HTJ2K_F)) {
+ do {
+ int newpasses1 = 0;
+
+ while (newpasses1 < newpasses_copy) {
+ newpasses1++;
+ if (needs_termination(codsty->cblk_style, npasses_copy + newpasses1 - 1)) {
+ cblk->nb_terminationsinc++;
+ break;
+ }
+ }
+ npasses_copy += newpasses1;
+ newpasses_copy -= newpasses1;
+ } while (newpasses_copy);
+ }
- while (newpasses1 < newpasses) {
- newpasses1 ++;
- if (needs_termination(codsty->cblk_style, cblk->npasses + newpasses1 - 1)) {
- cblk->nb_terminationsinc ++;
- break;
+ if (cblk->ht_plhd) {
+ href_passes = (cblk->npasses + newpasses - 1) % 3;
+ segment_passes = newpasses - href_passes;
+ pass_bound = 2;
+ bits_to_read = cblk->lblock;
+ if (segment_passes < 1) {
+ // No possible HT Cleanup pass here; may have placeholder passes
+ // or an original J2K block bit-stream (in MIXED mode).
+ segment_passes = newpasses;
+ while (pass_bound <= segment_passes) {
+ bits_to_read++;
+ pass_bound += pass_bound;
+ }
+ segment_bytes = get_bits(s, bits_to_read);
+ if (segment_bytes) {
+ if (cblk->modes & HT_MIXED) {
+ cblk->ht_plhd = HT_PLHD_OFF;
+ cblk->modes &= (uint8_t) (~(JPEG2000_CTSY_HTJ2K_F));
+ }
+ else {
+ av_log(s->avctx, AV_LOG_WARNING, "Length information for a HT-codeblock is invalid\n");
+ }
+ }
+ } else {
+ while (pass_bound <= segment_passes) {
+ bits_to_read++;
+ pass_bound += pass_bound;
+ }
+ segment_bytes = get_bits(s, bits_to_read);
+ if (segment_bytes) {
+ // No more placeholder passes
+ if (!(cblk->modes & HT_MIXED)) {
+ // Must be the first HT Cleanup pass
+ if (segment_bytes < 2)
+ av_log(s->avctx, AV_LOG_WARNING, "Length information for a HT-codeblock is invalid\n");
+ next_segment_passes = 2;
+ cblk->ht_plhd = HT_PLHD_OFF;
+ // Write length information for HT CleanUp segment
+ cblk->pass_lengths[0] = segment_bytes;
+ } else if (cblk->lblock > 3 && segment_bytes > 1
+ && (segment_bytes >> (bits_to_read - 1)) == 0) {
+ // Must be the first HT Cleanup pass, since length MSB is 0
+ next_segment_passes = 2;
+ cblk->ht_plhd = HT_PLHD_OFF;
+ // Write length information for HT CleanUp segment
+ cblk->pass_lengths[0] = segment_bytes;
+ } else {
+ // Must have an original (non-HT) block coding pass
+ cblk->modes &= (uint8_t) (~(JPEG2000_CTSY_HTJ2K_F));
+ cblk->ht_plhd = HT_PLHD_OFF;
+ segment_passes = newpasses;
+ while (pass_bound <= segment_passes) {
+ bits_to_read++;
+ pass_bound += pass_bound;
+ segment_bytes <<= 1;
+ segment_bytes += get_bits(s, 1);
+ }
+ }
+ } else {
+ // Probably parsing placeholder passes, but we need to read an
+ // extra length bit to verify this, since prior to the first
+ // HT Cleanup pass, the number of length bits read for a
+ // contributing code-block is dependent on the number of passes
+ // being included, as if it were a non-HT code-block.
+ segment_passes = newpasses;
+ if (pass_bound <= segment_passes) {
+ while (1) {
+ bits_to_read++;
+ pass_bound += pass_bound;
+ segment_bytes <<= 1;
+ segment_bytes += get_bits(s, 1);
+ if (pass_bound > segment_passes)
+ break;
+ }
+ if (segment_bytes) {
+ if (cblk->modes & HT_MIXED) {
+ cblk->modes &= (uint8_t) (~(JPEG2000_CTSY_HTJ2K_F));
+ cblk->ht_plhd = HT_PLHD_OFF;
+ } else {
+ av_log(s->avctx, AV_LOG_WARNING, "Length information for a HT-codeblock is invalid\n");
+ }
+ }
+ }
+ }
+ }
+ } else if (cblk->modes & JPEG2000_CTSY_HTJ2K_F) {
+ // Quality layer commences with a non-initial HT coding pass
+ if(bits_to_read != 0)
+ av_log(s->avctx, AV_LOG_WARNING, "Length information for a HT-codeblock is invalid\n");
+ segment_passes = cblk->npasses % 3;
+ if (segment_passes == 0) {
+ // newpasses is a HT Cleanup pass; next segment has refinement passes
+ segment_passes = 1;
+ next_segment_passes = 2;
+ if (segment_bytes == 1)
+ av_log(s->avctx, AV_LOG_WARNING, "Length information for a HT-codeblock is invalid\n");
+ } else {
+ // newpasses = 1 means npasses is HT SigProp; 2 means newpasses is
+ // HT MagRef pass
+ segment_passes = newpasses > 1 ? 3 - segment_passes : 1;
+ next_segment_passes = 1;
+ bits_to_read = av_log2(segment_passes);
+ }
+ bits_to_read = (uint8_t) (bits_to_read + cblk->lblock);
+ segment_bytes = get_bits(s, bits_to_read);
+ // Write length information for HT Refinment segment
+ cblk->pass_lengths[1] += segment_bytes;
+ } else if (!(cblk->modes & (JPEG2000_CBLK_TERMALL | JPEG2000_CBLK_BYPASS))) {
+ // Common case for non-HT code-blocks; we have only one segment
+ bits_to_read = (uint8_t) cblk->lblock + av_log2((uint8_t) newpasses);
+ segment_bytes = get_bits(s, bits_to_read);
+ segment_passes = newpasses;
+ } else if (cblk->modes & JPEG2000_CBLK_TERMALL) {
+ // RESTART MODE
+ bits_to_read = cblk->lblock;
+ segment_bytes = get_bits(s, bits_to_read);
+ segment_passes = 1;
+ next_segment_passes = 1;
+ } else {
+ // BYPASS MODE
+ bypass_term_threshold = 10;
+ if(bits_to_read != 0)
+ av_log(s->avctx, AV_LOG_WARNING, "Length information for a codeblock is invalid\n");
+ if (cblk->npasses < bypass_term_threshold) {
+ // May have from 1 to 10 uninterrupted passes before 1st RAW SigProp
+ segment_passes = bypass_term_threshold - cblk->npasses;
+ if (segment_passes > newpasses)
+ segment_passes = newpasses;
+ while ((2 << bits_to_read) <= segment_passes)
+ bits_to_read++;
+ next_segment_passes = 2;
+ } else if ((cblk->npasses - bypass_term_threshold) % 3 < 2) {
+ // 0 means newpasses is a RAW SigProp; 1 means newpasses is a RAW MagRef pass
+ segment_passes = newpasses > 1 ? 2 - (cblk->npasses - bypass_term_threshold) % 3 : 1;
+ bits_to_read = av_log2(segment_passes);
+ next_segment_passes = 1;
+ } else {
+ // newpasses is an isolated Cleanup pass that precedes a RAW SigProp pass
+ segment_passes = 1;
+ next_segment_passes = 2;
}
+ bits_to_read = (uint8_t) (bits_to_read + cblk->lblock);
+ segment_bytes = get_bits(s, bits_to_read);
}
-
- if (newpasses > 1 && (codsty->cblk_style & JPEG2000_CTSY_HTJ2K_F)) {
- // Retrieve pass lengths for each pass
- int href_passes = (cblk->npasses + newpasses - 1) % 3;
- int eb = av_log2(newpasses - href_passes);
- int extra_bit = newpasses > 2 ? 1 : 0;
- if ((ret = get_bits(s, llen + eb + 3)) < 0)
- return ret;
- cblk->pass_lengths[0] = ret;
- if ((ret = get_bits(s, llen + 3 + extra_bit)) < 0)
- return ret;
- cblk->pass_lengths[1] = ret;
- ret = cblk->pass_lengths[0] + cblk->pass_lengths[1];
+ // Update cblk->npasses and write length information
+ cblk->npasses = (uint8_t) (cblk->npasses + segment_passes);
+ cblk->lengthinc[cblk->nb_lengthinc++] = segment_bytes;
+
+ if ((cblk->modes & JPEG2000_CTSY_HTJ2K_F) && cblk->ht_plhd == HT_PLHD_OFF) {
+ newpasses -= (uint8_t) segment_passes;
+ while (newpasses > 0) {
+ segment_passes = newpasses > 1 ? next_segment_passes : 1;
+ next_segment_passes = (uint8_t) (3 - next_segment_passes);
+ bits_to_read = (uint8_t) (cblk->lblock + av_log2(segment_passes));
+ segment_bytes = get_bits(s, bits_to_read);
+ newpasses -= (uint8_t) (segment_passes);
+ // This is a FAST Refinement pass
+ // Write length information for HT Refinement segment
+ cblk->pass_lengths[1] += segment_bytes;
+ // Update cblk->npasses and write length information
+ cblk->npasses = (uint8_t) (cblk->npasses + segment_passes);
+ cblk->lengthinc[cblk->nb_lengthinc++] = segment_bytes;
+ }
} else {
- if ((ret = get_bits(s, av_log2(newpasses1) + cblk->lblock)) < 0)
- return ret;
- cblk->pass_lengths[0] = ret;
+ newpasses -= (uint8_t) (segment_passes);
+ while (newpasses > 0) {
+ if (bypass_term_threshold != 0) {
+ segment_passes = newpasses > 1 ? next_segment_passes : 1;
+ next_segment_passes = (uint8_t) (3 - next_segment_passes);
+ bits_to_read = (uint8_t) (cblk->lblock + av_log2(segment_passes));
+ } else {
+ if ((cblk->modes & JPEG2000_CBLK_TERMALL) == 0)
+ av_log(s->avctx, AV_LOG_WARNING, "Corrupted packet header is found.\n");
+ segment_passes = 1;
+ bits_to_read = cblk->lblock;
+ }
+ segment_bytes = get_bits(s, bits_to_read);
+ newpasses -= (uint8_t) (segment_passes);
+
+ // Update cblk->npasses and write length information
+ cblk->npasses = (uint8_t) (cblk->npasses + segment_passes);
+ cblk->lengthinc[cblk->nb_lengthinc++] = segment_bytes;
+ }
}
- if (ret > cblk->data_allocated) {
- size_t new_size = FFMAX(2*cblk->data_allocated, ret);
+
+ for (int i = 0; i < cblk->nb_lengthinc; ++i)
+ tmp_length = (tmp_length < cblk->lengthinc[i]) ? cblk->lengthinc[i] : tmp_length;
+
+ if (tmp_length > cblk->data_allocated) {
+ size_t new_size = FFMAX(2 * cblk->data_allocated, tmp_length);
void *new = av_realloc(cblk->data, new_size);
if (new) {
cblk->data = new;
cblk->data_allocated = new_size;
}
}
- if (ret > cblk->data_allocated) {
+ if (tmp_length > cblk->data_allocated) {
avpriv_request_sample(s->avctx,
"Block with lengthinc greater than %"SIZE_SPECIFIER"",
cblk->data_allocated);
return AVERROR_PATCHWELCOME;
}
- cblk->lengthinc[cblk->nb_lengthinc++] = ret;
- cblk->npasses += newpasses1;
- newpasses -= newpasses1;
- } while(newpasses);
+ } else {
+ // This codeblock has no contribution to the current packet
+ continue;
+ }
}
}
jpeg2000_flush(s);
@@ -1788,7 +1990,7 @@ static int decode_cblk(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *cod
Jpeg2000T1Context *t1, Jpeg2000Cblk *cblk,
int width, int height, int bandpos, uint8_t roi_shift)
{
- int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1 + roi_shift;
+ int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1;
int pass_cnt = 0;
int vert_causal_ctx_csty_symbol = codsty->cblk_style & JPEG2000_CBLK_VSC;
int term_cnt = 0;
@@ -2028,7 +2230,7 @@ static inline int tile_codeblocks(const Jpeg2000DecoderContext *s, Jpeg2000Tile
Jpeg2000Cblk *cblk = prec->cblk + cblkno;
- if (codsty->cblk_style & JPEG2000_CTSY_HTJ2K_F)
+ if (cblk->modes & JPEG2000_CTSY_HTJ2K_F)
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],
diff --git a/libavcodec/jpeg2000htdec.c b/libavcodec/jpeg2000htdec.c
index eba0936089..9b473e11d3 100644
--- a/libavcodec/jpeg2000htdec.c
+++ b/libavcodec/jpeg2000htdec.c
@@ -1032,25 +1032,31 @@ static void jpeg2000_calc_mbr(uint8_t *mbr, const uint16_t i, const uint16_t j,
static void jpeg2000_process_stripes_block(StateVars *sig_prop, int i_s, int j_s,
int width, int height, int stride, int pLSB,
int32_t *sample_buf, uint8_t *block_states,
- uint8_t *magref_segment, uint32_t magref_length)
+ uint8_t *magref_segment, uint32_t magref_length,
+ uint8_t is_causal)
{
for (int j = j_s; j < j_s + width; j++) {
uint32_t mbr_info = 0;
for (int i = i_s; i < i_s + height; i++) {
- int modify_state, cond;
+ int modify_state;
uint8_t bit;
- uint8_t causal_cond = i != (i_s + height - 1);
+ uint8_t causal_cond = (is_causal == 0) || (i != (i_s + height - 1));
int32_t *sp = &sample_buf[j + (i * (stride))];
uint8_t mbr = 0;
- if (jpeg2000_get_state(i, j, stride - 2, HT_SHIFT_SIGMA, block_states) == 0)
+ if (jpeg2000_get_state(i, j, stride, HT_SHIFT_SIGMA, block_states) == 0)
jpeg2000_calc_mbr(&mbr, i, j, mbr_info & 0x1EF, causal_cond, block_states, stride);
mbr_info >>= 3;
- cond = mbr != 0;
- bit = jpeg2000_peek_bit(sig_prop, magref_segment, magref_length);
- *sp |= (bit * cond) << pLSB;
- sig_prop->bits -= cond;
- modify_state = (((1 << HT_SHIFT_REF_IND) | (1 << HT_SHIFT_REF)) * cond) | 1 << HT_SHIFT_SCAN;
+
+ modify_state = block_states[(i + 1) * stride + (j + 1)];
+ modify_state |= 1 << HT_SHIFT_SCAN;
+ if (mbr != 0) {
+ modify_state |= 1 << HT_SHIFT_REF_IND;
+ bit = jpeg2000_peek_bit(sig_prop, magref_segment, magref_length);
+ modify_state |= bit << HT_SHIFT_REF;
+ *sp |= bit << pLSB;
+ *sp |= bit << (pLSB - 1); // Add 0.5 (reconstruction parameter = 1/2)
+ }
jpeg2000_modify_state(i, j, stride, modify_state, block_states);
}
}
@@ -1074,6 +1080,7 @@ static void jpeg2000_decode_sigprop_segment(Jpeg2000Cblk *cblk, uint16_t width,
int last_width;
uint16_t i = 0, j = 0;
+ uint8_t is_causal = cblk->modes & JPEG2000_CBLK_VSC;
jpeg2000_init_zero(&sp_dec);
@@ -1082,14 +1089,14 @@ static void jpeg2000_decode_sigprop_segment(Jpeg2000Cblk *cblk, uint16_t width,
for (int n2 = 0; n2 < num_h_stripe; n2++) {
jpeg2000_process_stripes_block(&sp_dec, i, j, b_width, b_height, stride,
pLSB, sample_buf, block_states, magref_segment,
- magref_length);
+ magref_length, is_causal);
j += 4;
}
last_width = width % 4;
if (last_width)
jpeg2000_process_stripes_block(&sp_dec, i, j, last_width, b_height, stride,
pLSB, sample_buf, block_states, magref_segment,
- magref_length);
+ magref_length, is_causal);
i += 4;
}
@@ -1099,20 +1106,20 @@ static void jpeg2000_decode_sigprop_segment(Jpeg2000Cblk *cblk, uint16_t width,
for (int n2 = 0; n2 < num_h_stripe; n2++) {
jpeg2000_process_stripes_block(&sp_dec, i, j, b_width, b_height, stride,
pLSB, sample_buf, block_states, magref_segment,
- magref_length);
+ magref_length, is_causal);
j += 4;
}
last_width = width % 4;
if (last_width)
jpeg2000_process_stripes_block(&sp_dec, i, j, last_width, b_height, stride,
pLSB, sample_buf, block_states, magref_segment,
- magref_length);
+ magref_length, is_causal);
}
/**
* See procedure decodeSigPropMag at Rec. ITU-T T.814, 7.5.
*/
-static int
+static void
jpeg2000_decode_magref_segment( uint16_t width, uint16_t block_height, const int stride,
uint8_t *magref_segment,uint32_t magref_length,
uint8_t pLSB, int32_t *sample_buf, uint8_t *block_states)
@@ -1152,15 +1159,14 @@ jpeg2000_decode_magref_segment( uint16_t width, uint16_t block_height, const int
}
}
}
- return 1;
}
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 width, int height, int M_b, uint8_t roi_shift)
{
- uint8_t p0 = 0; // Number of placeholder passes
+ uint8_t p0 = 0; // 3 * p0 = Number of placeholder passes
uint32_t Lcup; // Length of HT cleanup segment
uint32_t Lref; // Length of Refinement segment
uint32_t Scup; // HT cleanup segment suffix length
@@ -1174,7 +1180,7 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
int z_blk; // Number of ht coding pass
- uint8_t empty_passes;
+ uint8_t num_plhd_passes; // Number of placeholder passes
StateVars mag_sgn; // Magnitude and Sign
StateVars mel; // Adaptive run-length coding
@@ -1190,8 +1196,9 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
uint8_t *block_states = NULL;
int32_t n, val; // Post-processing
-
- int32_t M_b = magp;
+ const uint32_t mask = UINT32_MAX >> (M_b + 1); // bit mask for ROI detection
+
+ uint8_t num_rempass;
const int quad_buf_width = width + 4;
const int quad_buf_height = height + 4;
@@ -1201,22 +1208,17 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
av_assert0(width * height <= 4096);
av_assert0(width * height > 0);
- if (roi_shift)
- avpriv_report_missing_feature(s->avctx, "ROI shift");
-
memset(t1->data, 0, t1->stride * height * sizeof(*t1->data));
memset(t1->flags, 0, t1->stride * (height + 2) * sizeof(*t1->flags));
if (cblk->npasses == 0)
return 0;
- if (cblk->npasses > 3)
- p0 = 0;
- else if (cblk->length == 0)
- p0 = 1;
-
- empty_passes = p0 * 3;
- z_blk = cblk->npasses - empty_passes;
+ num_rempass = cblk->npasses % 3; // Number of remainder passes
+ num_plhd_passes = num_rempass ? cblk->npasses - num_rempass : cblk->npasses - 3;
+ av_assert0(num_plhd_passes % 3 == 0);
+ p0 = num_plhd_passes / 3;
+ z_blk = cblk->npasses - num_plhd_passes;
if (z_blk <= 0)
return 0; // No passes within this set, continue
@@ -1232,6 +1234,7 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
Dcup = cblk->data;
Dref = cblk->data + Lcup; // Dref comes after the refinement segment
S_blk = p0 + cblk->zbp;
+ cblk->zbp = S_blk - 1;
pLSB = 30 - S_blk;
Scup = (Dcup[Lcup - 1] << 4) + (Dcup[Lcup - 2] & 0x0F);
@@ -1277,31 +1280,32 @@ ff_jpeg2000_decode_htj2k(const Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c
goto free;
}
- if (cblk->npasses > 1)
+ if (z_blk > 1)
jpeg2000_decode_sigprop_segment(cblk, width, height, quad_buf_width, Dref, Lref,
pLSB - 1, sample_buf, block_states);
- if (cblk->npasses > 2) {
-
- if (Lref < 2){
- av_log(s->avctx,AV_LOG_ERROR,"Invalid magnitude refinement length\n");
- ret = AVERROR_INVALIDDATA;
- goto free;
- }
- if ((ret = jpeg2000_decode_magref_segment(width, height, quad_buf_width, Dref, Lref,
- pLSB - 1, sample_buf, block_states)) < 0)
- goto free;
- }
+ if (z_blk > 2)
+ jpeg2000_decode_magref_segment(width, height, quad_buf_width, Dref, Lref,
+ pLSB - 1, sample_buf, block_states);
pLSB = 31 - M_b;
/* Reconstruct the sample values */
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
+ int32_t sign;
+
n = x + (y * t1->stride);
val = sample_buf[x + (y * quad_buf_width)];
+ sign = val & INT32_MIN;
+ val &= INT32_MAX;
+ /* ROI shift, if necessary */
+ if (roi_shift && (((uint32_t)val & ~mask) == 0))
+ val <<= roi_shift;
/* Convert sign-magnitude to two's complement. */
- val = val >> 31 ? 0x80000000 - val : val;
+ if (sign)
+ val = -val;
+ /* Shift down to 1 bit upper from decimal point for reconstruction value (= 0.5) */
val >>= (pLSB - 1);
t1->data[n] = val;
}
--
2.34.1
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