* 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);