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-rw-r--r--jdhuff.c74
-rw-r--r--jdphuff.c114
-rw-r--r--jpeglib.h4
3 files changed, 124 insertions, 68 deletions
diff --git a/jdhuff.c b/jdhuff.c
index 0d704a5..bc5d4fd 100644
--- a/jdhuff.c
+++ b/jdhuff.c
@@ -295,20 +295,10 @@ jpeg_fill_bit_buffer (bitread_working_state * state,
int nbits)
/* Load up the bit buffer to a depth of at least nbits */
{
- j_decompress_ptr cinfo = state->cinfo;
- if (cinfo->tile_decode &&
- cinfo->restart_interval == 0 &&
- cinfo->unread_marker >= 0xd0 &&
- cinfo->unread_marker <= 0xd7 &&
- nbits > bits_left
- ) {
- // Skip the restart marker.
- cinfo->marker->next_restart_num = cinfo->unread_marker - 0xd0;
- process_restart(cinfo);
- }
/* Copy heavily used state fields into locals (hopefully registers) */
register const JOCTET * next_input_byte = state->next_input_byte;
register size_t bytes_in_buffer = state->bytes_in_buffer;
+ j_decompress_ptr cinfo = state->cinfo;
/* Attempt to load at least MIN_GET_BITS bits into get_buffer. */
/* (It is assumed that no request will be for more than that many bits.) */
@@ -509,24 +499,20 @@ process_restart (j_decompress_ptr cinfo)
}
/*
- * Configure the Huffman decoder reader position and bit buffer.
+ * Save the current Huffman deocde position and the DC coefficients
+ * for each component into bitstream_offset and dc_info[], respectively.
*/
-GLOBAL(void)
-jpeg_configure_huffman_decoder(j_decompress_ptr cinfo,
- huffman_offset_data offset)
+METHODDEF(void)
+get_huffman_decoder_configuration(j_decompress_ptr cinfo,
+ huffman_offset_data *offset)
{
- unsigned int bitstream_offset = offset.bitstream_offset;
- int blkn, i;
-
- cinfo->restart_interval = 0;
- cinfo->unread_marker = 0;
-
- unsigned int byte_offset = bitstream_offset >> LOG_TWO_BIT_BUF_SIZE;
- unsigned int bit_in_bit_buffer =
- bitstream_offset & ((1 << LOG_TWO_BIT_BUF_SIZE) - 1);
-
- jset_input_stream_position_bit(cinfo, byte_offset,
- bit_in_bit_buffer, offset.get_buffer);
+ huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
+ short int *dc_info = offset->prev_dc;
+ int i;
+ jpeg_get_huffman_decoder_configuration(cinfo, offset);
+ for (i = 0; i < cinfo->comps_in_scan; i++) {
+ dc_info[i] = entropy->saved.last_dc_val[i];
+ }
}
/*
@@ -546,6 +532,10 @@ jpeg_get_huffman_decoder_configuration(j_decompress_ptr cinfo,
return;
}
+ // Save restarts_to_go and next_restart_num
+ offset->restarts_to_go = (unsigned short) entropy->restarts_to_go;
+ offset->next_restart_num = cinfo->marker->next_restart_num;
+
offset->bitstream_offset =
(jget_input_stream_position(cinfo) << LOG_TWO_BIT_BUF_SIZE)
+ entropy->bitstate.bits_left;
@@ -570,20 +560,28 @@ configure_huffman_decoder(j_decompress_ptr cinfo, huffman_offset_data offset)
}
/*
- * Save the current Huffman deocde position and the DC coefficients
- * for each component into bitstream_offset and dc_info[], respectively.
+ * Configure the Huffman decoder reader position and bit buffer.
*/
-METHODDEF(void)
-get_huffman_decoder_configuration(j_decompress_ptr cinfo,
- huffman_offset_data *offset)
+GLOBAL(void)
+jpeg_configure_huffman_decoder(j_decompress_ptr cinfo,
+ huffman_offset_data offset)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
- short int *dc_info = offset->prev_dc;
- int i;
- jpeg_get_huffman_decoder_configuration(cinfo, offset);
- for (i = 0; i < cinfo->comps_in_scan; i++) {
- dc_info[i] = entropy->saved.last_dc_val[i];
- }
+
+ // Restore restarts_to_go and next_restart_num
+ cinfo->unread_marker = 0;
+ entropy->restarts_to_go = offset.restarts_to_go;
+ cinfo->marker->next_restart_num = offset.next_restart_num;
+
+ unsigned int bitstream_offset = offset.bitstream_offset;
+ int blkn, i;
+
+ unsigned int byte_offset = bitstream_offset >> LOG_TWO_BIT_BUF_SIZE;
+ unsigned int bit_in_bit_buffer =
+ bitstream_offset & ((1 << LOG_TWO_BIT_BUF_SIZE) - 1);
+
+ jset_input_stream_position_bit(cinfo, byte_offset,
+ bit_in_bit_buffer, offset.get_buffer);
}
/*
diff --git a/jdphuff.c b/jdphuff.c
index a58cdd2..922017e 100644
--- a/jdphuff.c
+++ b/jdphuff.c
@@ -632,6 +632,52 @@ undoit:
}
/*
+ * Save the current Huffman deocde position and the DC coefficients
+ * for each component into bitstream_offset and dc_info[], respectively.
+ */
+METHODDEF(void)
+get_huffman_decoder_configuration(j_decompress_ptr cinfo,
+ huffman_offset_data *offset)
+{
+ int i;
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+ jpeg_get_huffman_decoder_configuration_progressive(cinfo, offset);
+ offset->EOBRUN = entropy->saved.EOBRUN;
+ for (i = 0; i < cinfo->comps_in_scan; i++)
+ offset->prev_dc[i] = entropy->saved.last_dc_val[i];
+}
+
+
+/*
+ * Save the current Huffman decoder position and the bit buffer
+ * into bitstream_offset and get_buffer, respectively.
+ */
+GLOBAL(void)
+jpeg_get_huffman_decoder_configuration_progressive(j_decompress_ptr cinfo,
+ huffman_offset_data *offset)
+{
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+
+ if (cinfo->restart_interval) {
+ // We are at the end of a data segment
+ if (entropy->restarts_to_go == 0)
+ if (! process_restart(cinfo))
+ return;
+ }
+
+ // Save restarts_to_go and next_restart_num.
+ offset->restarts_to_go = (unsigned short) entropy->restarts_to_go;
+ offset->next_restart_num = cinfo->marker->next_restart_num;
+
+ offset->bitstream_offset =
+ (jget_input_stream_position(cinfo) << LOG_TWO_BIT_BUF_SIZE)
+ + entropy->bitstate.bits_left;
+
+ offset->get_buffer = entropy->bitstate.get_buffer;
+}
+
+
+/*
* Configure the Huffman decoder to decode the image
* starting from (iMCU_row_offset, iMCU_col_offset).
*/
@@ -640,32 +686,58 @@ configure_huffman_decoder(j_decompress_ptr cinfo, huffman_offset_data offset)
{
int i;
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- jpeg_configure_huffman_decoder(cinfo, offset);
+ jpeg_configure_huffman_decoder_progressive(cinfo, offset);
entropy->saved.EOBRUN = offset.EOBRUN;
for (i = 0; i < cinfo->comps_in_scan; i++)
entropy->saved.last_dc_val[i] = offset.prev_dc[i];
}
/*
- * Save the current Huffman deocde position and the DC coefficients
- * for each component into bitstream_offset and dc_info[], respectively.
+ * Configure the Huffman decoder reader position and bit buffer.
*/
-METHODDEF(void)
-get_huffman_decoder_configuration(j_decompress_ptr cinfo,
- huffman_offset_data *offset)
+GLOBAL(void)
+jpeg_configure_huffman_decoder_progressive(j_decompress_ptr cinfo,
+ huffman_offset_data offset)
+{
+ phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
+
+ // Restore restarts_to_go and next_restart_num
+ cinfo->unread_marker = 0;
+ entropy->restarts_to_go = offset.restarts_to_go;
+ cinfo->marker->next_restart_num = offset.next_restart_num;
+
+ unsigned int bitstream_offset = offset.bitstream_offset;
+ int blkn, i;
+
+ unsigned int byte_offset = bitstream_offset >> LOG_TWO_BIT_BUF_SIZE;
+ unsigned int bit_in_bit_buffer =
+ bitstream_offset & ((1 << LOG_TWO_BIT_BUF_SIZE) - 1);
+
+ jset_input_stream_position_bit(cinfo, byte_offset,
+ bit_in_bit_buffer, offset.get_buffer);
+}
+
+GLOBAL(void)
+jpeg_configure_huffman_index_scan(j_decompress_ptr cinfo,
+ huffman_index *index, int scan_no, int offset)
{
- int i;
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- jpeg_get_huffman_decoder_configuration(cinfo, offset);
- offset->EOBRUN = entropy->saved.EOBRUN;
- for (i = 0; i < cinfo->comps_in_scan; i++)
- offset->prev_dc[i] = entropy->saved.last_dc_val[i];
+ if (scan_no >= index->scan_count) {
+ index->scan = realloc(index->scan,
+ (scan_no + 1) * sizeof(huffman_scan_header));
+ index->mem_used += (scan_no - index->scan_count + 1)
+ * (sizeof(huffman_scan_header) + cinfo->total_iMCU_rows
+ * sizeof(huffman_offset_data*));
+ index->scan_count = scan_no + 1;
+ }
+ index->scan[scan_no].offset = (huffman_offset_data**)malloc(
+ cinfo->total_iMCU_rows * sizeof(huffman_offset_data*));
+ index->scan[scan_no].bitstream_offset = offset;
}
/*
* Module initialization routine for progressive Huffman entropy decoding.
*/
-
GLOBAL(void)
jinit_phuff_decoder (j_decompress_ptr cinfo)
{
@@ -697,22 +769,4 @@ jinit_phuff_decoder (j_decompress_ptr cinfo)
*coef_bit_ptr++ = -1;
}
-GLOBAL(void)
-jpeg_configure_huffman_index_scan(j_decompress_ptr cinfo,
- huffman_index *index, int scan_no, int offset)
-{
- phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
- if (scan_no >= index->scan_count) {
- index->scan = realloc(index->scan,
- (scan_no + 1) * sizeof(huffman_scan_header));
- index->mem_used += (scan_no - index->scan_count + 1)
- * (sizeof(huffman_scan_header) + cinfo->total_iMCU_rows
- * sizeof(huffman_offset_data*));
- index->scan_count = scan_no + 1;
- }
- index->scan[scan_no].offset = (huffman_offset_data**)malloc(
- cinfo->total_iMCU_rows * sizeof(huffman_offset_data*));
- index->scan[scan_no].bitstream_offset = offset;
-}
-
#endif /* D_PROGRESSIVE_SUPPORTED */
diff --git a/jpeglib.h b/jpeglib.h
index 83bed4a..07e6872 100644
--- a/jpeglib.h
+++ b/jpeglib.h
@@ -649,6 +649,10 @@ typedef struct {
// save the decoder current bit buffer, entropy->bitstate.get_buffer.
INT32 get_buffer;
+
+ // save the restart info.
+ unsigned short restarts_to_go;
+ unsigned char next_restart_num;
} huffman_offset_data;
typedef struct {
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-04 00:39:44 +0000