// Module initialization routine for Huffman entropy encoding.
static void jinit_shuff_encoder(jpeg_compress cinfo)
{
jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy = null;
try
{
entropy = new shuff_entropy_encoder();
entropy.saved.last_dc_val = new int[MAX_COMPS_IN_SCAN];
}
catch
{
ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
}
lossyc.entropy_private = entropy;
lossyc.entropy_start_pass = start_pass_huff;
lossyc.need_optimization_pass = need_optimization_pass_sq;
// Mark tables unallocated
for (int i = 0; i < NUM_HUFF_TBLS; i++)
{
entropy.dc_derived_tbls[i] = entropy.ac_derived_tbls[i] = null;
#if ENTROPY_OPT_SUPPORTED
entropy.dc_count_ptrs[i] = entropy.ac_count_ptrs[i] = null;
#endif
}
}
// Trial-encode one MCU's worth of Huffman-compressed coefficients.
// No data is actually output, so no suspension return is possible.
static bool encode_mcu_gather_sq(jpeg_compress cinfo, short[][] MCU_data)
{
jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy = (shuff_entropy_encoder)lossyc.entropy_private;
// Take care of restart intervals if needed
if (cinfo.restart_interval != 0)
{
if (entropy.restarts_to_go == 0)
{
// Re-initialize DC predictions to 0
for (int ci = 0; ci < cinfo.comps_in_scan; ci++)
{
entropy.saved.last_dc_val[ci] = 0;
}
// Update restart state
entropy.restarts_to_go = cinfo.restart_interval;
}
entropy.restarts_to_go--;
}
for (int blkn = 0; blkn < cinfo.block_in_MCU; blkn++)
{
int ci = cinfo.MCU_membership[blkn];
jpeg_component_info compptr = cinfo.cur_comp_info[ci];
htest_one_block_sq(cinfo, MCU_data[blkn], entropy.saved.last_dc_val[ci], entropy.dc_count_ptrs[compptr.dc_tbl_no], entropy.ac_count_ptrs[compptr.ac_tbl_no]);
entropy.saved.last_dc_val[ci] = MCU_data[blkn][0];
}
return(true);
}
// Finish up at the end of a Huffman-compressed scan.
static void finish_pass_huff_sq(jpeg_compress cinfo)
{
jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy = (shuff_entropy_encoder)lossyc.entropy_private;
working_state_sq state;
state.cur.last_dc_val = new int[MAX_COMPS_IN_SCAN];
// Load up working state ... flush_bits needs it
state.output_bytes = cinfo.dest.output_bytes;
state.next_output_byte = cinfo.dest.next_output_byte;
state.free_in_buffer = cinfo.dest.free_in_buffer;
state.cur = entropy.saved;
entropy.saved.last_dc_val.CopyTo(state.cur.last_dc_val, 0);
state.cinfo = cinfo;
// Flush out the last data
if (!flush_bits(ref state))
{
ERREXIT(cinfo, J_MESSAGE_CODE.JERR_CANT_SUSPEND);
}
// Update state
cinfo.dest.output_bytes = state.output_bytes;
cinfo.dest.next_output_byte = state.next_output_byte;
cinfo.dest.free_in_buffer = state.free_in_buffer;
entropy.saved = state.cur;
state.cur.last_dc_val.CopyTo(entropy.saved.last_dc_val, 0);
}
// Finish up a statistics-gathering pass and create the new Huffman tables.
static void finish_pass_gather_sq(jpeg_compress cinfo)
{
jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy = (shuff_entropy_encoder)lossyc.entropy_private;
// It's important not to apply jpeg_gen_optimal_table more than once
// per table, because it clobbers the input frequency counts!
bool[] did_dc = new bool[NUM_HUFF_TBLS];
bool[] did_ac = new bool[NUM_HUFF_TBLS];
for (int ci = 0; ci < cinfo.comps_in_scan; ci++)
{
jpeg_component_info compptr = cinfo.cur_comp_info[ci];
int dctbl = compptr.dc_tbl_no;
int actbl = compptr.ac_tbl_no;
if (!did_dc[dctbl])
{
if (cinfo.dc_huff_tbl_ptrs[dctbl] == null)
{
cinfo.dc_huff_tbl_ptrs[dctbl] = jpeg_alloc_huff_table(cinfo);
}
jpeg_gen_optimal_table(cinfo, cinfo.dc_huff_tbl_ptrs[dctbl], entropy.dc_count_ptrs[dctbl]);
did_dc[dctbl] = true;
}
if (!did_ac[actbl])
{
if (cinfo.ac_huff_tbl_ptrs[actbl] == null)
{
cinfo.ac_huff_tbl_ptrs[actbl] = jpeg_alloc_huff_table(cinfo);
}
jpeg_gen_optimal_table(cinfo, cinfo.ac_huff_tbl_ptrs[actbl], entropy.ac_count_ptrs[actbl]);
did_ac[actbl] = true;
}
}
}
// Module initialization routine for Huffman entropy encoding.
static void jinit_shuff_encoder(jpeg_compress cinfo)
{
jpeg_lossy_c_codec lossyc=(jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy=null;
try
{
entropy=new shuff_entropy_encoder();
entropy.saved.last_dc_val=new int[MAX_COMPS_IN_SCAN];
}
catch
{
ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
}
lossyc.entropy_private=entropy;
lossyc.entropy_start_pass=start_pass_huff;
lossyc.need_optimization_pass=need_optimization_pass_sq;
// Mark tables unallocated
for(int i=0; i<NUM_HUFF_TBLS; i++)
{
entropy.dc_derived_tbls[i]=entropy.ac_derived_tbls[i]=null;
#if ENTROPY_OPT_SUPPORTED
entropy.dc_count_ptrs[i]=entropy.ac_count_ptrs[i]=null;
#endif
}
}
// Initialize for a Huffman-compressed scan.
// If gather_statistics is true, we do not output anything during the scan,
// just count the Huffman symbols used and generate Huffman code tables.
static void start_pass_huff(jpeg_compress cinfo, bool gather_statistics)
{
jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy = (shuff_entropy_encoder)lossyc.entropy_private;
if (gather_statistics)
{
#if ENTROPY_OPT_SUPPORTED
lossyc.entropy_encode_mcu = encode_mcu_gather_sq;
lossyc.entropy_finish_pass = finish_pass_gather_sq;
#else
ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif
}
else
{
lossyc.entropy_encode_mcu = encode_mcu_huff_sq;
lossyc.entropy_finish_pass = finish_pass_huff_sq;
}
for (int ci = 0; ci < cinfo.comps_in_scan; ci++)
{
jpeg_component_info compptr = cinfo.cur_comp_info[ci];
int dctbl = compptr.dc_tbl_no;
int actbl = compptr.ac_tbl_no;
if (gather_statistics)
{
#if ENTROPY_OPT_SUPPORTED
// Check for invalid table indexes
// (make_c_derived_tbl does this in the other path)
if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS)
{
ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_NO_HUFF_TABLE, dctbl);
}
if (actbl < 0 || actbl >= NUM_HUFF_TBLS)
{
ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_NO_HUFF_TABLE, actbl);
}
// Allocate and zero the statistics tables
// Note that jpeg_gen_optimal_table expects 257 entries in each table!
if (entropy.dc_count_ptrs[dctbl] == null)
{
try
{
entropy.dc_count_ptrs[dctbl] = new int[257];
}
catch
{
ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
}
}
else
{
for (int i = 0; i < 257; i++)
{
entropy.dc_count_ptrs[dctbl][i] = 0;
}
}
if (entropy.ac_count_ptrs[actbl] == null)
{
try
{
entropy.ac_count_ptrs[actbl] = new int[257];
}
catch
{
ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
}
}
else
{
for (int i = 0; i < 257; i++)
{
entropy.ac_count_ptrs[actbl][i] = 0;
}
}
#endif
}
else
{
// Compute derived values for Huffman tables
// We may do this more than once for a table, but it's not expensive
jpeg_make_c_derived_tbl(cinfo, true, dctbl, ref entropy.dc_derived_tbls[dctbl]);
jpeg_make_c_derived_tbl(cinfo, false, actbl, ref entropy.ac_derived_tbls[actbl]);
}
// Initialize DC predictions to 0
entropy.saved.last_dc_val[ci] = 0;
}
// Initialize bit buffer to empty
entropy.saved.put_buffer = 0;
entropy.saved.put_bits = 0;
// Initialize restart stuff
entropy.restarts_to_go = cinfo.restart_interval;
entropy.next_restart_num = 0;
}
// Encode and output one MCU's worth of Huffman-compressed coefficients.
static bool encode_mcu_huff_sq(jpeg_compress cinfo, short[][] MCU_data)
{
jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
shuff_entropy_encoder entropy = (shuff_entropy_encoder)lossyc.entropy_private;
// Load up working state
working_state_sq state;
state.cur.last_dc_val = new int[MAX_COMPS_IN_SCAN];
state.output_bytes = cinfo.dest.output_bytes;
state.next_output_byte = cinfo.dest.next_output_byte;
state.free_in_buffer = cinfo.dest.free_in_buffer;
//was state.cur=entropy.saved;
state.cur.put_bits = entropy.saved.put_bits;
state.cur.put_buffer = entropy.saved.put_buffer;
entropy.saved.last_dc_val.CopyTo(state.cur.last_dc_val, 0);
state.cinfo = cinfo;
// Emit restart marker if needed
if (cinfo.restart_interval != 0)
{
if (entropy.restarts_to_go == 0)
{
if (!emit_restart(ref state, entropy.next_restart_num))
{
return(false);
}
}
}
// Encode the MCU data blocks
for (int blkn = 0; blkn < cinfo.block_in_MCU; blkn++)
{
int ci = cinfo.MCU_membership[blkn];
jpeg_component_info compptr = cinfo.cur_comp_info[ci];
if (!encode_one_block(ref state, MCU_data[blkn], state.cur.last_dc_val[ci], entropy.dc_derived_tbls[compptr.dc_tbl_no], entropy.ac_derived_tbls[compptr.ac_tbl_no]))
{
return(false);
}
// Update last_dc_val
state.cur.last_dc_val[ci] = MCU_data[blkn][0];
}
// Completed MCU, so update state
cinfo.dest.output_bytes = state.output_bytes;
cinfo.dest.next_output_byte = state.next_output_byte;
cinfo.dest.free_in_buffer = state.free_in_buffer;
//was entropy.saved=state.cur;
entropy.saved.put_bits = state.cur.put_bits;
entropy.saved.put_buffer = state.cur.put_buffer;
state.cur.last_dc_val.CopyTo(entropy.saved.last_dc_val, 0);
// Update restart-interval state too
if (cinfo.restart_interval != 0)
{
if (entropy.restarts_to_go == 0)
{
entropy.restarts_to_go = cinfo.restart_interval;
entropy.next_restart_num++;
entropy.next_restart_num &= 7;
}
entropy.restarts_to_go--;
}
return(true);
}
