#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#ifdef INPUT_SMOOTHING_SUPPORTED
#define CONTEXT_ROWS_SUPPORTED
#endif
typedef struct {
struct jpeg_c_prep_controller pub;
JSAMPARRAY color_buf[MAX_COMPONENTS];
JDIMENSION rows_to_go;
int next_buf_row;
#ifdef CONTEXT_ROWS_SUPPORTED
int this_row_group;
int next_buf_stop;
#endif
} my_prep_controller;
typedef my_prep_controller * my_prep_ptr;
METHODDEF(void)
start_pass_prep (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
if (pass_mode != JBUF_PASS_THRU)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
prep->rows_to_go = cinfo->image_height;
prep->next_buf_row = 0;
#ifdef CONTEXT_ROWS_SUPPORTED
prep->this_row_group = 0;
prep->next_buf_stop = 2 * cinfo->max_v_samp_factor;
#endif
}
LOCAL(void)
expand_bottom_edge (JSAMPARRAY image_data, JDIMENSION num_cols,
int input_rows, int output_rows)
{
register int row;
for (row = input_rows; row < output_rows; row++) {
jcopy_sample_rows(image_data, input_rows-1, image_data, row,
1, num_cols);
}
}
METHODDEF(void)
pre_process_data (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
JDIMENSION in_rows_avail,
JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
JDIMENSION out_row_groups_avail)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
int numrows, ci;
JDIMENSION inrows;
jpeg_component_info * compptr;
while (*in_row_ctr < in_rows_avail &&
*out_row_group_ctr < out_row_groups_avail) {
inrows = in_rows_avail - *in_row_ctr;
numrows = cinfo->max_v_samp_factor - prep->next_buf_row;
numrows = (int) MIN((JDIMENSION) numrows, inrows);
(*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,
prep->color_buf,
(JDIMENSION) prep->next_buf_row,
numrows);
*in_row_ctr += numrows;
prep->next_buf_row += numrows;
prep->rows_to_go -= numrows;
if (prep->rows_to_go == 0 &&
prep->next_buf_row < cinfo->max_v_samp_factor) {
for (ci = 0; ci < cinfo->num_components; ci++) {
expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
prep->next_buf_row, cinfo->max_v_samp_factor);
}
prep->next_buf_row = cinfo->max_v_samp_factor;
}
if (prep->next_buf_row == cinfo->max_v_samp_factor) {
(*cinfo->downsample->downsample) (cinfo,
prep->color_buf, (JDIMENSION) 0,
output_buf, *out_row_group_ctr);
prep->next_buf_row = 0;
(*out_row_group_ctr)++;
}
if (prep->rows_to_go == 0 &&
*out_row_group_ctr < out_row_groups_avail) {
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
numrows = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
cinfo->min_DCT_v_scaled_size;
expand_bottom_edge(output_buf[ci],
compptr->width_in_blocks * compptr->DCT_h_scaled_size,
(int) (*out_row_group_ctr * numrows),
(int) (out_row_groups_avail * numrows));
}
*out_row_group_ctr = out_row_groups_avail;
break;
}
}
}
#ifdef CONTEXT_ROWS_SUPPORTED
METHODDEF(void)
pre_process_context (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
JDIMENSION in_rows_avail,
JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
JDIMENSION out_row_groups_avail)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
int numrows, ci;
int buf_height = cinfo->max_v_samp_factor * 3;
JDIMENSION inrows;
while (*out_row_group_ctr < out_row_groups_avail) {
if (*in_row_ctr < in_rows_avail) {
inrows = in_rows_avail - *in_row_ctr;
numrows = prep->next_buf_stop - prep->next_buf_row;
numrows = (int) MIN((JDIMENSION) numrows, inrows);
(*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,
prep->color_buf,
(JDIMENSION) prep->next_buf_row,
numrows);
if (prep->rows_to_go == cinfo->image_height) {
for (ci = 0; ci < cinfo->num_components; ci++) {
int row;
for (row = 1; row <= cinfo->max_v_samp_factor; row++) {
jcopy_sample_rows(prep->color_buf[ci], 0,
prep->color_buf[ci], -row,
1, cinfo->image_width);
}
}
}
*in_row_ctr += numrows;
prep->next_buf_row += numrows;
prep->rows_to_go -= numrows;
} else {
if (prep->rows_to_go != 0)
break;
if (prep->next_buf_row < prep->next_buf_stop) {
for (ci = 0; ci < cinfo->num_components; ci++) {
expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
prep->next_buf_row, prep->next_buf_stop);
}
prep->next_buf_row = prep->next_buf_stop;
}
}
if (prep->next_buf_row == prep->next_buf_stop) {
(*cinfo->downsample->downsample) (cinfo,
prep->color_buf,
(JDIMENSION) prep->this_row_group,
output_buf, *out_row_group_ctr);
(*out_row_group_ctr)++;
prep->this_row_group += cinfo->max_v_samp_factor;
if (prep->this_row_group >= buf_height)
prep->this_row_group = 0;
if (prep->next_buf_row >= buf_height)
prep->next_buf_row = 0;
prep->next_buf_stop = prep->next_buf_row + cinfo->max_v_samp_factor;
}
}
}
LOCAL(void)
create_context_buffer (j_compress_ptr cinfo)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
int rgroup_height = cinfo->max_v_samp_factor;
int ci, i;
jpeg_component_info * compptr;
JSAMPARRAY true_buffer, fake_buffer;
fake_buffer = (JSAMPARRAY)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(cinfo->num_components * 5 * rgroup_height) *
SIZEOF(JSAMPROW));
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
true_buffer = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
(JDIMENSION) (((long) compptr->width_in_blocks *
cinfo->min_DCT_h_scaled_size *
cinfo->max_h_samp_factor) / compptr->h_samp_factor),
(JDIMENSION) (3 * rgroup_height));
MEMCOPY(fake_buffer + rgroup_height, true_buffer,
3 * rgroup_height * SIZEOF(JSAMPROW));
for (i = 0; i < rgroup_height; i++) {
fake_buffer[i] = true_buffer[2 * rgroup_height + i];
fake_buffer[4 * rgroup_height + i] = true_buffer[i];
}
prep->color_buf[ci] = fake_buffer + rgroup_height;
fake_buffer += 5 * rgroup_height;
}
}
#endif
GLOBAL(void)
jinit_c_prep_controller (j_compress_ptr cinfo, boolean need_full_buffer)
{
my_prep_ptr prep;
int ci;
jpeg_component_info * compptr;
if (need_full_buffer)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
prep = (my_prep_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_prep_controller));
cinfo->prep = (struct jpeg_c_prep_controller *) prep;
prep->pub.start_pass = start_pass_prep;
if (cinfo->downsample->need_context_rows) {
#ifdef CONTEXT_ROWS_SUPPORTED
prep->pub.pre_process_data = pre_process_context;
create_context_buffer(cinfo);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
prep->pub.pre_process_data = pre_process_data;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
prep->color_buf[ci] = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
(JDIMENSION) (((long) compptr->width_in_blocks *
cinfo->min_DCT_h_scaled_size *
cinfo->max_h_samp_factor) / compptr->h_samp_factor),
(JDIMENSION) cinfo->max_v_samp_factor);
}
}
}