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Diffstat (limited to 'src/imageutils/transupp.c')
| -rw-r--r-- | src/imageutils/transupp.c | 928 |
1 files changed, 928 insertions, 0 deletions
diff --git a/src/imageutils/transupp.c b/src/imageutils/transupp.c new file mode 100644 index 0000000..e5ec564 --- /dev/null +++ b/src/imageutils/transupp.c @@ -0,0 +1,928 @@ +/* + * transupp.c + * + * Copyright (C) 1997, Thomas G. Lane. + * 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. + */ + +/* 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 */ + + +#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. + * + * 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. + * + * 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. 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. + * Notes 2,3,4 boil down to this: generally we should use the destination's + * dimensions and ignore the source's. + */ + + +LOCAL(void) +do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo, + jvirt_barray_ptr *src_coef_arrays) +/* Horizontal flip; done in-place, so no separate dest array is required */ +{ + JDIMENSION MCU_cols, comp_width, blk_x, blk_y; + 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 = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE); + + for (ci = 0; ci < dstinfo->num_components; ci++) { + compptr = dstinfo->comp_info + ci; + comp_width = MCU_cols * 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++) { + 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; + } + } + } + } + } +} + + +LOCAL(void) +do_flip_v (j_decompress_ptr srcinfo, j_compress_ptr dstinfo, + 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; + 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 = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE); + + for (ci = 0; ci < dstinfo->num_components; ci++) { + compptr = dstinfo->comp_info + ci; + comp_height = MCU_rows * 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 (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 - 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, + (JDIMENSION) compptr->v_samp_factor, FALSE); + } + for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) { + if (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]; + 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], dst_buffer[offset_y], + compptr->width_in_blocks); + } + } + } + } +} + + +LOCAL(void) +do_transpose (j_decompress_ptr srcinfo, j_compress_ptr dstinfo, + jvirt_barray_ptr *src_coef_arrays, + jvirt_barray_ptr *dst_coef_arrays) +/* Transpose source into destination */ +{ + JDIMENSION dst_blk_x, dst_blk_y; + 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; + 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, + (JDIMENSION) compptr->h_samp_factor, FALSE); + for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) { + src_ptr = src_buffer[offset_x][dst_blk_y + offset_y]; + dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x]; + 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, + 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; + 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 = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE); + + for (ci = 0; ci < dstinfo->num_components; ci++) { + compptr = dstinfo->comp_info + ci; + comp_width = MCU_cols * compptr->h_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, + (JDIMENSION) compptr->h_samp_factor, FALSE); + for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) { + src_ptr = src_buffer[offset_x][dst_blk_y + offset_y]; + if (dst_blk_x < comp_width) { + /* Block is within the mirrorable area. */ + dst_ptr = dst_buffer[offset_y] + [comp_width - dst_blk_x - offset_x - 1]; + 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. */ + dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x]; + 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, + 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; + 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 = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE); + + for (ci = 0; ci < dstinfo->num_components; ci++) { + compptr = dstinfo->comp_info + ci; + comp_height = MCU_rows * 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, + (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 (dst_blk_y < comp_height) { + /* Block is within the mirrorable area. */ + src_ptr = src_buffer[offset_x] + [comp_height - 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]; + 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, + 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; + 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 = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE); + MCU_rows = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE); + + 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; + 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 (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 - 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, + (JDIMENSION) compptr->v_samp_factor, FALSE); + } + for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) { + if (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]; + /* Process the blocks that can be mirrored both ways. */ + for (dst_blk_x = 0; dst_blk_x < comp_width; dst_blk_x++) { + dst_ptr = dst_row_ptr[dst_blk_x]; + src_ptr = src_row_ptr[comp_width - 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++; + } + } + } + /* Any remaining right-edge blocks are only mirrored vertically. */ + for (; 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) { + 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. */ + dst_row_ptr = dst_buffer[offset_y]; + src_row_ptr = src_buffer[offset_y]; + /* Process the blocks that can be mirrored. */ + for (dst_blk_x = 0; dst_blk_x < comp_width; dst_blk_x++) { + dst_ptr = dst_row_ptr[dst_blk_x]; + src_ptr = src_row_ptr[comp_width - dst_blk_x - 1]; + for (i = 0; i < DCTSIZE2; i += 2) { + *dst_ptr++ = *src_ptr++; + *dst_ptr++ = - *src_ptr++; + } + } + /* Any remaining right-edge blocks are only copied. */ + for (; 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 < DCTSIZE2; i++) + *dst_ptr++ = *src_ptr++; + } + } + } + } + } +} + + +LOCAL(void) +do_transverse (j_decompress_ptr srcinfo, j_compress_ptr dstinfo, + 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; + int ci, i, j, offset_x, offset_y; + JBLOCKARRAY src_buffer, dst_buffer; + JCOEFPTR src_ptr, dst_ptr; + jpeg_component_info *compptr; + + MCU_cols = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE); + MCU_rows = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE); + + 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; + 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, + (JDIMENSION) compptr->h_samp_factor, FALSE); + for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) { + if (dst_blk_y < comp_height) { + src_ptr = src_buffer[offset_x] + [comp_height - dst_blk_y - offset_y - 1]; + if (dst_blk_x < comp_width) { + /* Block is within the mirrorable area. */ + dst_ptr = dst_buffer[offset_y] + [comp_width - dst_blk_x - offset_x - 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 */ + dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x]; + 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 { + src_ptr = src_buffer[offset_x][dst_blk_y + offset_y]; + if (dst_blk_x < comp_width) { + /* Bottom-edge blocks are mirrored in x only */ + dst_ptr = dst_buffer[offset_y] + [comp_width - dst_blk_x - offset_x - 1]; + 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 { + /* At lower right corner, just transpose, no mirroring */ + dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x]; + for (i = 0; i < DCTSIZE; i++) + for (j = 0; j < DCTSIZE; j++) + dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j]; + } + } + } + } + } + } + } +} + + +/* Request any required workspace. + * + * We allocate the workspace virtual arrays from the source decompression + * object, so that all the arrays (both the original data and the workspace) + * will be taken into account while making memory management decisions. + * Hence, this routine must be called after jpeg_read_header (which reads + * the image dimensions) and before jpeg_read_coefficients (which realizes + * the source's virtual arrays). + */ + +GLOBAL(void) +jtransform_request_workspace (j_decompress_ptr srcinfo, + jpeg_transform_info *info) +{ + jvirt_barray_ptr *coef_arrays = NULL; + jpeg_component_info *compptr; + int ci; + + if (info->force_grayscale && + srcinfo->jpeg_color_space == JCS_YCbCr && + srcinfo->num_components == 3) { + /* We'll only process the first component */ + info->num_components = 1; + } else { + /* Process all the components */ + info->num_components = srcinfo->num_components; + } + + switch (info->transform) { + case JXFORM_NONE: + case JXFORM_FLIP_H: + /* Don't need a workspace array */ + break; + case JXFORM_FLIP_V: + case JXFORM_ROT_180: + /* Need workspace arrays having same dimensions as source image. + * Note that we allocate arrays padded out to the next iMCU boundary, + * so that transform routines need not worry about missing edge blocks. + */ + coef_arrays = (jvirt_barray_ptr *) + (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE, + SIZEOF(jvirt_barray_ptr) * info->num_components); + for (ci = 0; ci < info->num_components; ci++) { + compptr = srcinfo->comp_info + ci; + coef_arrays[ci] = (*srcinfo->mem->request_virt_barray) + ((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE, + (JDIMENSION) jround_up((long) compptr->width_in_blocks, + (long) compptr->h_samp_factor), + (JDIMENSION) jround_up((long) compptr->height_in_blocks, + (long) compptr->v_samp_factor), + (JDIMENSION) compptr->v_samp_factor); + } + break; + case JXFORM_TRANSPOSE: + case JXFORM_TRANSVERSE: + case JXFORM_ROT_90: + case JXFORM_ROT_270: + /* Need workspace arrays having transposed dimensions. + * Note that we allocate arrays padded out to the next iMCU boundary, + * so that transform routines need not worry about missing edge blocks. + */ + coef_arrays = (jvirt_barray_ptr *) + (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE, + SIZEOF(jvirt_barray_ptr) * info->num_components); + for (ci = 0; ci < info->num_components; ci++) { + compptr = srcinfo->comp_info + ci; + coef_arrays[ci] = (*srcinfo->mem->request_virt_barray) + ((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE, + (JDIMENSION) jround_up((long) compptr->height_in_blocks, + (long) compptr->v_samp_factor), + (JDIMENSION) jround_up((long) compptr->width_in_blocks, + (long) compptr->h_samp_factor), + (JDIMENSION) compptr->h_samp_factor); + } + break; + } + info->workspace_coef_arrays = coef_arrays; +} + + +/* Transpose destination image parameters */ + +LOCAL(void) +transpose_critical_parameters (j_compress_ptr dstinfo) +{ + int tblno, i, j, ci, itemp; + jpeg_component_info *compptr; + JQUANT_TBL *qtblptr; + JDIMENSION dtemp; + UINT16 qtemp; + + /* Transpose basic image dimensions */ + dtemp = dstinfo->image_width; + dstinfo->image_width = dstinfo->image_height; + dstinfo->image_height = dtemp; + + /* Transpose sampling factors */ + for (ci = 0; ci < dstinfo->num_components; ci++) { + compptr = dstinfo->comp_info + ci; + itemp = compptr->h_samp_factor; + compptr->h_samp_factor = compptr->v_samp_factor; + compptr->v_samp_factor = itemp; + } + + /* Transpose quantization tables */ + for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) { + qtblptr = dstinfo->quant_tbl_ptrs[tblno]; + if (qtblptr != NULL) { + for (i = 0; i < DCTSIZE; i++) { + for (j = 0; j < i; j++) { + qtemp = qtblptr->quantval[i*DCTSIZE+j]; + qtblptr->quantval[i*DCTSIZE+j] = qtblptr->quantval[j*DCTSIZE+i]; + qtblptr->quantval[j*DCTSIZE+i] = qtemp; + } + } + } + } +} + + +/* Trim off any partial iMCUs on the indicated destination edge */ + +LOCAL(void) +trim_right_edge (j_compress_ptr dstinfo) +{ + int ci, max_h_samp_factor; + JDIMENSION MCU_cols; + + /* We have to compute max_h_samp_factor ourselves, + * because it hasn't been set yet in the destination + * (and we don't want to use the source's value). + */ + max_h_samp_factor = 1; + for (ci = 0; ci < dstinfo->num_components; ci++) { + int h_samp_factor = dstinfo->comp_info[ci].h_samp_factor; + max_h_samp_factor = MAX(max_h_samp_factor, h_samp_factor); + } + MCU_cols = dstinfo->image_width / (max_h_samp_factor * DCTSIZE); + if (MCU_cols > 0) /* can't trim to 0 pixels */ + dstinfo->image_width = MCU_cols * (max_h_samp_factor * DCTSIZE); +} + +LOCAL(void) +trim_bottom_edge (j_compress_ptr dstinfo) +{ + int ci, max_v_samp_factor; + JDIMENSION MCU_rows; + + /* We have to compute max_v_samp_factor ourselves, + * because it hasn't been set yet in the destination + * (and we don't want to use the source's value). + */ + max_v_samp_factor = 1; + for (ci = 0; ci < dstinfo->num_components; ci++) { + int v_samp_factor = dstinfo->comp_info[ci].v_samp_factor; + max_v_samp_factor = MAX(max_v_samp_factor, v_samp_factor); + } + MCU_rows = dstinfo->image_height / (max_v_samp_factor * DCTSIZE); + if (MCU_rows > 0) /* can't trim to 0 pixels */ + dstinfo->image_height = MCU_rows * (max_v_samp_factor * DCTSIZE); +} + + +/* Adjust output image parameters as needed. + * + * This must be called after jpeg_copy_critical_parameters() + * and before jpeg_write_coefficients(). + * + * The return value is the set of virtual coefficient arrays to be written + * (either the ones allocated by jtransform_request_workspace, or the + * original source data arrays). The caller will need to pass this value + * to jpeg_write_coefficients(). + */ + +GLOBAL(jvirt_barray_ptr *) +jtransform_adjust_parameters (j_decompress_ptr srcinfo, + j_compress_ptr dstinfo, + jvirt_barray_ptr *src_coef_arrays, + jpeg_transform_info *info) +{ + /* If force-to-grayscale is requested, adjust destination parameters */ + if (info->force_grayscale) { + /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed + * properly. Among other things, the target h_samp_factor & v_samp_factor + * will get set to 1, which typically won't match the source. + * In fact we do this even if the source is already grayscale; that + * provides an easy way of coercing a grayscale JPEG with funny sampling + * factors to the customary 1,1. (Some decoders fail on other factors.) + */ + if ((dstinfo->jpeg_color_space == JCS_YCbCr && + dstinfo->num_components == 3) || + (dstinfo->jpeg_color_space == JCS_GRAYSCALE && + dstinfo->num_components == 1)) { + /* We have to preserve the source's quantization table number. */ + int sv_quant_tbl_no = dstinfo->comp_info[0].quant_tbl_no; + jpeg_set_colorspace(dstinfo, JCS_GRAYSCALE); + dstinfo->comp_info[0].quant_tbl_no = sv_quant_tbl_no; + } else { + /* Sorry, can't do it */ + ERREXIT(dstinfo, JERR_CONVERSION_NOTIMPL); + } + } + + /* Correct the destination's image dimensions etc if necessary */ + switch (info->transform) { + case JXFORM_NONE: + /* Nothing to do */ + break; + case JXFORM_FLIP_H: + if (info->trim) + trim_right_edge(dstinfo); + break; + case JXFORM_FLIP_V: + if (info->trim) + trim_bottom_edge(dstinfo); + break; + case JXFORM_TRANSPOSE: + transpose_critical_parameters(dstinfo); + /* transpose does NOT have to trim anything */ + break; + case JXFORM_TRANSVERSE: + transpose_critical_parameters(dstinfo); + if (info->trim) { + trim_right_edge(dstinfo); + trim_bottom_edge(dstinfo); + } + break; + case JXFORM_ROT_90: + transpose_critical_parameters(dstinfo); + if (info->trim) + trim_right_edge(dstinfo); + break; + case JXFORM_ROT_180: + if (info->trim) { + trim_right_edge(dstinfo); + trim_bottom_edge(dstinfo); + } + break; + case JXFORM_ROT_270: + transpose_critical_parameters(dstinfo); + if (info->trim) + trim_bottom_edge(dstinfo); + break; + } + + /* Return the appropriate output data set */ + if (info->workspace_coef_arrays != NULL) + return info->workspace_coef_arrays; + return src_coef_arrays; +} + + +/* Execute the actual transformation, if any. + * + * This must be called *after* jpeg_write_coefficients, because it depends + * on jpeg_write_coefficients to have computed subsidiary values such as + * the per-component width and height fields in the destination object. + * + * Note that some transformations will modify the source data arrays! + */ + +GLOBAL(void) +jtransform_execute_transformation (j_decompress_ptr srcinfo, + j_compress_ptr dstinfo, + jvirt_barray_ptr *src_coef_arrays, + jpeg_transform_info *info) +{ + jvirt_barray_ptr *dst_coef_arrays = info->workspace_coef_arrays; + + switch (info->transform) { + case JXFORM_NONE: + break; + case JXFORM_FLIP_H: + do_flip_h(srcinfo, dstinfo, src_coef_arrays); + break; + case JXFORM_FLIP_V: + do_flip_v(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays); + break; + case JXFORM_TRANSPOSE: + do_transpose(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays); + break; + case JXFORM_TRANSVERSE: + do_transverse(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays); + break; + case JXFORM_ROT_90: + do_rot_90(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays); + break; + case JXFORM_ROT_180: + do_rot_180(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays); + break; + case JXFORM_ROT_270: + do_rot_270(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays); + break; + } +} + +#endif /* TRANSFORMS_SUPPORTED */ + + +/* Setup decompression object to save desired markers in memory. + * This must be called before jpeg_read_header() to have the desired effect. + */ + +GLOBAL(void) +jcopy_markers_setup (j_decompress_ptr srcinfo, JCOPY_OPTION option) +{ +#ifdef SAVE_MARKERS_SUPPORTED + int m; + + /* Save comments except under NONE option */ + if (option != JCOPYOPT_NONE) { + jpeg_save_markers(srcinfo, JPEG_COM, 0xFFFF); + } + /* Save all types of APPn markers iff ALL option */ + if (option == JCOPYOPT_ALL) { + for (m = 0; m < 16; m++) + jpeg_save_markers(srcinfo, JPEG_APP0 + m, 0xFFFF); + } +#endif /* SAVE_MARKERS_SUPPORTED */ +} + +/* Copy markers saved in the given source object to the destination object. + * This should be called just after jpeg_start_compress() or + * jpeg_write_coefficients(). + * Note that those routines will have written the SOI, and also the + * JFIF APP0 or Adobe APP14 markers if selected. + */ + +GLOBAL(void) +jcopy_markers_execute (j_decompress_ptr srcinfo, j_compress_ptr dstinfo, + JCOPY_OPTION option) +{ + jpeg_saved_marker_ptr marker; + + /* In the current implementation, we don't actually need to examine the + * option flag here; we just copy everything that got saved. + * But to avoid confusion, we do not output JFIF and Adobe APP14 markers + * if the encoder library already wrote one. + */ + for (marker = srcinfo->marker_list; marker != NULL; marker = marker->next) { + if (dstinfo->write_JFIF_header && + marker->marker == JPEG_APP0 && + marker->data_length >= 5 && + GETJOCTET(marker->data[0]) == 0x4A && + GETJOCTET(marker->data[1]) == 0x46 && + GETJOCTET(marker->data[2]) == 0x49 && + GETJOCTET(marker->data[3]) == 0x46 && + GETJOCTET(marker->data[4]) == 0) + continue; /* reject duplicate JFIF */ + if (dstinfo->write_Adobe_marker && + marker->marker == JPEG_APP0+14 && + marker->data_length >= 5 && + GETJOCTET(marker->data[0]) == 0x41 && + GETJOCTET(marker->data[1]) == 0x64 && + GETJOCTET(marker->data[2]) == 0x6F && + GETJOCTET(marker->data[3]) == 0x62 && + GETJOCTET(marker->data[4]) == 0x65) + continue; /* reject duplicate Adobe */ +#ifdef NEED_FAR_POINTERS + /* We could use jpeg_write_marker if the data weren't FAR... */ + { + unsigned int i; + jpeg_write_m_header(dstinfo, marker->marker, marker->data_length); + for (i = 0; i < marker->data_length; i++) + jpeg_write_m_byte(dstinfo, marker->data[i]); + } +#else + jpeg_write_marker(dstinfo, marker->marker, + marker->data, marker->data_length); +#endif + } +} |