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transupp.c
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transupp.c
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/*
* transupp.c
*
* Copyright (C) 1997-2017, Thomas G. Lane, Guido Vollbeding.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains image transformation routines and other utility code
* used by the jpegtran sample application. These are NOT part of the core
* JPEG library. But we keep these routines separate from jpegtran.c to
* ease the task of maintaining jpegtran-like programs that have other user
* interfaces.
*/
/*
* Pixelization extension
*
* Copyright (C) 2022, Kame
* This file is modified for implement pixelization function extension.
*/
/* Although this file really shouldn't have access to the library internals,
* it's helpful to let it call jround_up() and jcopy_block_row().
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "transupp.h" /* My own external interface */
#include <ctype.h> /* to declare isdigit() */
#if TRANSFORMS_SUPPORTED
/*
* Lossless image transformation routines. These routines work on DCT
* coefficient arrays and thus do not require any lossy decompression
* or recompression of the image.
* Thanks to Guido Vollbeding for the initial design and code of this feature,
* and to Ben Jackson for introducing the cropping feature.
*
* Horizontal flipping is done in-place, using a single top-to-bottom
* pass through the virtual source array. It will thus be much the
* fastest option for images larger than main memory.
*
* The other routines require a set of destination virtual arrays, so they
* need twice as much memory as jpegtran normally does. The destination
* arrays are always written in normal scan order (top to bottom) because
* the virtual array manager expects this. The source arrays will be scanned
* in the corresponding order, which means multiple passes through the source
* arrays for most of the transforms. That could result in much thrashing
* if the image is larger than main memory.
*
* If cropping or trimming is involved, the destination arrays may be smaller
* than the source arrays. Note it is not possible to do horizontal flip
* in-place when a nonzero Y crop offset is specified, since we'd have to move
* data from one block row to another but the virtual array manager doesn't
* guarantee we can touch more than one row at a time. So in that case,
* we have to use a separate destination array.
*
* Some notes about the operating environment of the individual transform
* routines:
* 1. Both the source and destination virtual arrays are allocated from the
* source JPEG object, and therefore should be manipulated by calling the
* source's memory manager.
* 2. The destination's component count should be used. It may be smaller
* than the source's when forcing to grayscale.
* 3. Likewise the destination's sampling factors should be used. When
* forcing to grayscale the destination's sampling factors will be all 1,
* and we may as well take that as the effective iMCU size.
* 4. When "trim" is in effect, the destination's dimensions will be the
* trimmed values but the source's will be untrimmed.
* 5. When "crop" is in effect, the destination's dimensions will be the
* cropped values but the source's will be uncropped. Each transform
* routine is responsible for picking up source data starting at the
* correct X and Y offset for the crop region. (The X and Y offsets
* passed to the transform routines are measured in iMCU blocks of the
* destination.)
* 6. All the routines assume that the source and destination buffers are
* padded out to a full iMCU boundary. This is true, although for the
* source buffer it is an undocumented property of jdcoefct.c.
*/
LOCAL(void)
do_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Crop. This is only used when no rotate/flip is requested with the crop. */
{
JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;
int ci, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
jpeg_component_info *compptr;
/* We simply have to copy the right amount of data (the destination's
* image size) starting at the given X and Y offsets in the source.
*/
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks,
(JDIMENSION) compptr->v_samp_factor, FALSE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
dst_buffer[offset_y],
compptr->width_in_blocks);
}
}
}
}
LOCAL(void)
do_crop_ext (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Crop. This is only used when no rotate/flip is requested with the crop.
* Extension: If the destination size is larger than the source, we fill in
* the extra area with zero (neutral gray). Note we also have to zero partial
* iMCUs at the right and bottom edge of the source image area in this case.
*/
{
JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height;
JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;
int ci, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
jpeg_component_info *compptr;
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
MCU_rows = srcinfo->output_height /
(dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
if (dstinfo->jpeg_height > srcinfo->output_height) {
if (dst_blk_y < y_crop_blocks ||
dst_blk_y >= comp_height + y_crop_blocks) {
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
FMEMZERO(dst_buffer[offset_y],
compptr->width_in_blocks * SIZEOF(JBLOCK));
}
continue;
}
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_y - y_crop_blocks,
(JDIMENSION) compptr->v_samp_factor, FALSE);
} else {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks,
(JDIMENSION) compptr->v_samp_factor, FALSE);
}
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
if (dstinfo->jpeg_width > srcinfo->output_width) {
if (x_crop_blocks > 0) {
FMEMZERO(dst_buffer[offset_y],
x_crop_blocks * SIZEOF(JBLOCK));
}
jcopy_block_row(src_buffer[offset_y],
dst_buffer[offset_y] + x_crop_blocks,
comp_width);
if (compptr->width_in_blocks > comp_width + x_crop_blocks) {
FMEMZERO(dst_buffer[offset_y] +
comp_width + x_crop_blocks,
(compptr->width_in_blocks -
comp_width - x_crop_blocks) * SIZEOF(JBLOCK));
}
} else {
jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
dst_buffer[offset_y],
compptr->width_in_blocks);
}
}
}
}
}
LOCAL(void)
do_wipe (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Wipe - drop content of specified area, fill with zero (neutral gray) */
{
JDIMENSION x_wipe_blocks, wipe_width;
JDIMENSION y_wipe_blocks, wipe_bottom;
int ci, offset_y;
JBLOCKARRAY buffer;
jpeg_component_info *compptr;
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
y_wipe_blocks = y_crop_offset * compptr->v_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor + y_wipe_blocks;
for (; y_wipe_blocks < wipe_bottom;
y_wipe_blocks += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci], y_wipe_blocks,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
FMEMZERO(buffer[offset_y] + x_wipe_blocks,
wipe_width * SIZEOF(JBLOCK));
}
}
}
}
LOCAL(void)
do_flatten (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Flatten - drop content of specified area, similar to wipe,
* but fill with average of adjacent blocks, instead of zero.
*/
{
JDIMENSION x_wipe_blocks, wipe_width, wipe_right;
JDIMENSION y_wipe_blocks, wipe_bottom, blk_x;
int ci, offset_y, dc_left_value, dc_right_value, average;
JBLOCKARRAY buffer;
jpeg_component_info *compptr;
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
wipe_right = wipe_width + x_wipe_blocks;
y_wipe_blocks = y_crop_offset * compptr->v_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor + y_wipe_blocks;
for (; y_wipe_blocks < wipe_bottom;
y_wipe_blocks += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci], y_wipe_blocks,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
FMEMZERO(buffer[offset_y] + x_wipe_blocks,
wipe_width * SIZEOF(JBLOCK));
if (x_wipe_blocks > 0) {
dc_left_value = buffer[offset_y][x_wipe_blocks - 1][0];
if (wipe_right < compptr->width_in_blocks) {
dc_right_value = buffer[offset_y][wipe_right][0];
average = (dc_left_value + dc_right_value) >> 1;
} else {
average = dc_left_value;
}
} else if (wipe_right < compptr->width_in_blocks) {
average = buffer[offset_y][wipe_right][0];
} else continue;
for (blk_x = x_wipe_blocks; blk_x < wipe_right; blk_x++) {
buffer[offset_y][blk_x][0] = (JCOEF) average;
}
}
}
}
}
/* Added for ajpegtran
* This function perform pixelize.
* Based on do_wipe() function above.
* This fucntion clear AC coefficients only, whereas do_wipe() clear all coefficient.
*/
LOCAL(void)
do_pixelize (j_decompress_ptr srcinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Wipe - drop content of specified area, fill with zero (neutral gray) */
{
JDIMENSION x_wipe_blocks, wipe_width;
JDIMENSION y_wipe_blocks, wipe_bottom;
int ci, offset_y,offset_x;
JBLOCKARRAY buffer;
jpeg_component_info *compptr;
for (ci = 0; ci < srcinfo->num_components; ci++) {
compptr = srcinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
y_wipe_blocks = y_crop_offset * compptr->v_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor + y_wipe_blocks;
for (; y_wipe_blocks < wipe_bottom;
y_wipe_blocks += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci], y_wipe_blocks,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
for (offset_x = x_wipe_blocks; offset_x < x_wipe_blocks+wipe_width; offset_x++) {
JCOEF *blktop = buffer[offset_y][offset_x];
FMEMZERO(blktop+1, (DCTSIZE2-1) * SIZEOF(JCOEF));
}
}
}
}
}
/* Added for jpegtran extension
* This function perform pixelize
* Based on do_pixelize() function above.
* This fucntion averag DC coefficients in pixelized block.
*/
LOCAL(void)
do_pixelize2 (j_decompress_ptr srcinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height,
JDIMENSION pix_blk_ratio_x, JDIMENSION pix_blk_ratio_y,
boolean blk_align)
{
JDIMENSION x_wipe_blocks, wipe_width;
JDIMENSION y_wipe_blocks, wipe_bottom;
int ci, offset_y,offset_x;
JBLOCKARRAY buffer;
jpeg_component_info *compptr;
int mcu_ratio_x, mcu_ratio_y;
int mcu_blk_x,mcu_blk_y;
mcu_ratio_x = pix_blk_ratio_x;
mcu_ratio_y = pix_blk_ratio_y;
for (ci = 0; ci < srcinfo->num_components; ci++) {
compptr = srcinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
y_wipe_blocks = y_crop_offset * compptr->v_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor + y_wipe_blocks;
mcu_blk_x = compptr->h_samp_factor * mcu_ratio_x;
mcu_blk_y = compptr->v_samp_factor * mcu_ratio_y;
JDIMENSION wipe_height = drop_height * compptr->v_samp_factor;
int step_x=mcu_blk_x,step_y=mcu_blk_y;
int start_x=0,start_y=0;
if( blk_align ){
/* Block Align mode */
start_y = y_wipe_blocks % mcu_blk_y;
step_y = mcu_blk_y - start_y;
}
for (offset_y = 0; offset_y < wipe_height; offset_y+=step_y) {
if( offset_y ) step_y = mcu_blk_y;
if( blk_align ){
/* Block Align mode */
start_x = x_wipe_blocks % mcu_blk_x;
step_x = mcu_blk_x - start_x;
}
for (offset_x = x_wipe_blocks; offset_x < x_wipe_blocks+wipe_width; offset_x+=step_x) {
int ave=0,num=0;
if( offset_x > x_wipe_blocks ) step_x = mcu_blk_x;
for( int local_y = 0 ; local_y<step_y && offset_y+local_y < wipe_height ; local_y++ ){
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci], y_wipe_blocks+offset_y+local_y,
(JDIMENSION) 1, TRUE);
for( int local_x = 0 ; local_x<step_x && offset_x+local_x < x_wipe_blocks+wipe_width ; local_x++ ){
JCOEF *blktop = buffer[0][offset_x+local_x];
ave += blktop[0];
num++;
FMEMZERO(blktop+1, (DCTSIZE2-1) * SIZEOF(JCOEF));
}
}
ave /= num;
for( int local_y = 0 ; local_y<step_y && offset_y+local_y < wipe_height ; local_y++ ){
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci], y_wipe_blocks+offset_y+local_y,
(JDIMENSION) 1, TRUE);
for( int local_x = 0 ; local_x<step_x && offset_x+local_x < x_wipe_blocks+wipe_width ; local_x++ ){
buffer[0][offset_x+local_x][0] = ave;
}
}
start_x = 0;
}
start_y = 0;
}
}
}
LOCAL(void)
do_flip_h_no_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset,
jvirt_barray_ptr *src_coef_arrays)
/* Horizontal flip; done in-place, so no separate dest array is required.
* NB: this only works when y_crop_offset is zero.
*/
{
JDIMENSION MCU_cols, comp_width, blk_x, blk_y, x_crop_blocks;
int ci, k, offset_y;
JBLOCKARRAY buffer;
JCOEFPTR ptr1, ptr2;
JCOEF temp1, temp2;
jpeg_component_info *compptr;
/* Horizontal mirroring of DCT blocks is accomplished by swapping
* pairs of blocks in-place. Within a DCT block, we perform horizontal
* mirroring by changing the signs of odd-numbered columns.
* Partial iMCUs at the right edge are left untouched.
*/
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
for (blk_y = 0; blk_y < compptr->height_in_blocks;
blk_y += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci], blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
/* Do the mirroring */
for (blk_x = 0; blk_x * 2 < comp_width; blk_x++) {
ptr1 = buffer[offset_y][blk_x];
ptr2 = buffer[offset_y][comp_width - blk_x - 1];
/* this unrolled loop doesn't need to know which row it's on... */
for (k = 0; k < DCTSIZE2; k += 2) {
temp1 = *ptr1; /* swap even column */
temp2 = *ptr2;
*ptr1++ = temp2;
*ptr2++ = temp1;
temp1 = *ptr1; /* swap odd column with sign change */
temp2 = *ptr2;
*ptr1++ = -temp2;
*ptr2++ = -temp1;
}
}
if (x_crop_blocks > 0) {
/* Now left-justify the portion of the data to be kept.
* We can't use a single jcopy_block_row() call because that routine
* depends on memcpy(), whose behavior is unspecified for overlapping
* source and destination areas. Sigh.
*/
for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {
jcopy_block_row(buffer[offset_y] + blk_x + x_crop_blocks,
buffer[offset_y] + blk_x,
(JDIMENSION) 1);
}
}
}
}
}
}
LOCAL(void)
do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Horizontal flip in general cropping case */
{
JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
JDIMENSION x_crop_blocks, y_crop_blocks;
int ci, k, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JBLOCKROW src_row_ptr, dst_row_ptr;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
/* Here we must output into a separate array because we can't touch
* different rows of a single virtual array simultaneously. Otherwise,
* this is essentially the same as the routine above.
*/
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks,
(JDIMENSION) compptr->v_samp_factor, FALSE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
dst_row_ptr = dst_buffer[offset_y];
src_row_ptr = src_buffer[offset_y];
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Do the mirrorable blocks */
dst_ptr = dst_row_ptr[dst_blk_x];
src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
/* this unrolled loop doesn't need to know which row it's on... */
for (k = 0; k < DCTSIZE2; k += 2) {
*dst_ptr++ = *src_ptr++; /* copy even column */
*dst_ptr++ = - *src_ptr++; /* copy odd column with sign change */
}
} else {
/* Copy last partial block(s) verbatim */
jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
dst_row_ptr + dst_blk_x,
(JDIMENSION) 1);
}
}
}
}
}
}
LOCAL(void)
do_flip_v (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Vertical flip */
{
JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
JDIMENSION x_crop_blocks, y_crop_blocks;
int ci, i, j, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JBLOCKROW src_row_ptr, dst_row_ptr;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
/* We output into a separate array because we can't touch different
* rows of the source virtual array simultaneously. Otherwise, this
* is a pretty straightforward analog of horizontal flip.
* Within a DCT block, vertical mirroring is done by changing the signs
* of odd-numbered rows.
* Partial iMCUs at the bottom edge are copied verbatim.
*/
MCU_rows = srcinfo->output_height /
(dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
if (y_crop_blocks + dst_blk_y < comp_height) {
/* Row is within the mirrorable area. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
comp_height - y_crop_blocks - dst_blk_y -
(JDIMENSION) compptr->v_samp_factor,
(JDIMENSION) compptr->v_samp_factor, FALSE);
} else {
/* Bottom-edge blocks will be copied verbatim. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks,
(JDIMENSION) compptr->v_samp_factor, FALSE);
}
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
if (y_crop_blocks + dst_blk_y < comp_height) {
/* Row is within the mirrorable area. */
dst_row_ptr = dst_buffer[offset_y];
src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
src_row_ptr += x_crop_blocks;
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
dst_blk_x++) {
dst_ptr = dst_row_ptr[dst_blk_x];
src_ptr = src_row_ptr[dst_blk_x];
for (i = 0; i < DCTSIZE; i += 2) {
/* copy even row */
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = *src_ptr++;
/* copy odd row with sign change */
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = - *src_ptr++;
}
}
} else {
/* Just copy row verbatim. */
jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
dst_buffer[offset_y],
compptr->width_in_blocks);
}
}
}
}
}
LOCAL(void)
do_transpose (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Transpose source into destination */
{
JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;
int ci, i, j, offset_x, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
/* Transposing pixels within a block just requires transposing the
* DCT coefficients.
* Partial iMCUs at the edges require no special treatment; we simply
* process all the available DCT blocks for every component.
*/
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
dst_blk_x += compptr->h_samp_factor) {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_x + x_crop_blocks,
(JDIMENSION) compptr->h_samp_factor, FALSE);
for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
src_ptr = src_buffer[offset_x][dst_blk_y + offset_y + y_crop_blocks];
for (i = 0; i < DCTSIZE; i++)
for (j = 0; j < DCTSIZE; j++)
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
}
}
}
}
}
}
LOCAL(void)
do_rot_90 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* 90 degree rotation is equivalent to
* 1. Transposing the image;
* 2. Horizontal mirroring.
* These two steps are merged into a single processing routine.
*/
{
JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
JDIMENSION x_crop_blocks, y_crop_blocks;
int ci, i, j, offset_x, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
/* Because of the horizontal mirror step, we can't process partial iMCUs
* at the (output) right edge properly. They just get transposed and
* not mirrored.
*/
MCU_cols = srcinfo->output_height /
(dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
dst_blk_x += compptr->h_samp_factor) {
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Block is within the mirrorable area. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
comp_width - x_crop_blocks - dst_blk_x -
(JDIMENSION) compptr->h_samp_factor,
(JDIMENSION) compptr->h_samp_factor, FALSE);
} else {
/* Edge blocks are transposed but not mirrored. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_x + x_crop_blocks,
(JDIMENSION) compptr->h_samp_factor, FALSE);
}
for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Block is within the mirrorable area. */
src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
[dst_blk_y + offset_y + y_crop_blocks];
for (i = 0; i < DCTSIZE; i++) {
for (j = 0; j < DCTSIZE; j++)
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
i++;
for (j = 0; j < DCTSIZE; j++)
dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
}
} else {
/* Edge blocks are transposed but not mirrored. */
src_ptr = src_buffer[offset_x]
[dst_blk_y + offset_y + y_crop_blocks];
for (i = 0; i < DCTSIZE; i++)
for (j = 0; j < DCTSIZE; j++)
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
}
}
}
}
}
}
}
LOCAL(void)
do_rot_270 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* 270 degree rotation is equivalent to
* 1. Horizontal mirroring;
* 2. Transposing the image.
* These two steps are merged into a single processing routine.
*/
{
JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
JDIMENSION x_crop_blocks, y_crop_blocks;
int ci, i, j, offset_x, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
/* Because of the horizontal mirror step, we can't process partial iMCUs
* at the (output) bottom edge properly. They just get transposed and
* not mirrored.
*/
MCU_rows = srcinfo->output_width /
(dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
dst_blk_x += compptr->h_samp_factor) {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_x + x_crop_blocks,
(JDIMENSION) compptr->h_samp_factor, FALSE);
for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
if (y_crop_blocks + dst_blk_y < comp_height) {
/* Block is within the mirrorable area. */
src_ptr = src_buffer[offset_x]
[comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
for (i = 0; i < DCTSIZE; i++) {
for (j = 0; j < DCTSIZE; j++) {
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
j++;
dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
}
}
} else {
/* Edge blocks are transposed but not mirrored. */
src_ptr = src_buffer[offset_x]
[dst_blk_y + offset_y + y_crop_blocks];
for (i = 0; i < DCTSIZE; i++)
for (j = 0; j < DCTSIZE; j++)
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
}
}
}
}
}
}
}
LOCAL(void)
do_rot_180 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* 180 degree rotation is equivalent to
* 1. Vertical mirroring;
* 2. Horizontal mirroring.
* These two steps are merged into a single processing routine.
*/
{
JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
JDIMENSION x_crop_blocks, y_crop_blocks;
int ci, i, j, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JBLOCKROW src_row_ptr, dst_row_ptr;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
MCU_rows = srcinfo->output_height /
(dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
if (y_crop_blocks + dst_blk_y < comp_height) {
/* Row is within the vertically mirrorable area. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
comp_height - y_crop_blocks - dst_blk_y -
(JDIMENSION) compptr->v_samp_factor,
(JDIMENSION) compptr->v_samp_factor, FALSE);
} else {
/* Bottom-edge rows are only mirrored horizontally. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks,
(JDIMENSION) compptr->v_samp_factor, FALSE);
}
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
dst_row_ptr = dst_buffer[offset_y];
if (y_crop_blocks + dst_blk_y < comp_height) {
/* Row is within the mirrorable area. */
src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
dst_ptr = dst_row_ptr[dst_blk_x];
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Process the blocks that can be mirrored both ways. */
src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
for (i = 0; i < DCTSIZE; i += 2) {
/* For even row, negate every odd column. */
for (j = 0; j < DCTSIZE; j += 2) {
*dst_ptr++ = *src_ptr++;
*dst_ptr++ = - *src_ptr++;
}
/* For odd row, negate every even column. */
for (j = 0; j < DCTSIZE; j += 2) {
*dst_ptr++ = - *src_ptr++;
*dst_ptr++ = *src_ptr++;
}
}
} else {
/* Any remaining right-edge blocks are only mirrored vertically. */
src_ptr = src_row_ptr[x_crop_blocks + dst_blk_x];
for (i = 0; i < DCTSIZE; i += 2) {
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = *src_ptr++;
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = - *src_ptr++;
}
}
}
} else {
/* Remaining rows are just mirrored horizontally. */
src_row_ptr = src_buffer[offset_y];
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Process the blocks that can be mirrored. */
dst_ptr = dst_row_ptr[dst_blk_x];
src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
for (i = 0; i < DCTSIZE2; i += 2) {
*dst_ptr++ = *src_ptr++;
*dst_ptr++ = - *src_ptr++;
}
} else {
/* Any remaining right-edge blocks are only copied. */
jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
dst_row_ptr + dst_blk_x,
(JDIMENSION) 1);
}
}
}
}
}
}
}
LOCAL(void)
do_transverse (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Transverse transpose is equivalent to
* 1. 180 degree rotation;
* 2. Transposition;
* or
* 1. Horizontal mirroring;
* 2. Transposition;
* 3. Horizontal mirroring.
* These steps are merged into a single processing routine.
*/
{
JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
JDIMENSION x_crop_blocks, y_crop_blocks;
int ci, i, j, offset_x, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
MCU_cols = srcinfo->output_height /
(dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
MCU_rows = srcinfo->output_width /
(dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION) compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
dst_blk_x += compptr->h_samp_factor) {
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Block is within the mirrorable area. */
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
comp_width - x_crop_blocks - dst_blk_x -
(JDIMENSION) compptr->h_samp_factor,
(JDIMENSION) compptr->h_samp_factor, FALSE);
} else {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr) srcinfo, src_coef_arrays[ci],
dst_blk_x + x_crop_blocks,
(JDIMENSION) compptr->h_samp_factor, FALSE);
}
for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
if (y_crop_blocks + dst_blk_y < comp_height) {
if (x_crop_blocks + dst_blk_x < comp_width) {
/* Block is within the mirrorable area. */
src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
[comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
for (i = 0; i < DCTSIZE; i++) {
for (j = 0; j < DCTSIZE; j++) {
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
j++;
dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
}
i++;
for (j = 0; j < DCTSIZE; j++) {
dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
j++;
dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
}
}
} else {
/* Right-edge blocks are mirrored in y only */
src_ptr = src_buffer[offset_x]
[comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
for (i = 0; i < DCTSIZE; i++) {
for (j = 0; j < DCTSIZE; j++) {