📄 transupp.c
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is_motorola = TRUE; else return; /* Check Tag Mark */ if (is_motorola) { if (GETJOCTET(data[2]) != 0) return; if (GETJOCTET(data[3]) != 0x2A) return; } else { if (GETJOCTET(data[3]) != 0) return; if (GETJOCTET(data[2]) != 0x2A) return; } /* Get first IFD offset (offset to IFD0) */ if (is_motorola) { if (GETJOCTET(data[4]) != 0) return; if (GETJOCTET(data[5]) != 0) return; firstoffset = GETJOCTET(data[6]); firstoffset <<= 8; firstoffset += GETJOCTET(data[7]); } else { if (GETJOCTET(data[7]) != 0) return; if (GETJOCTET(data[6]) != 0) return; firstoffset = GETJOCTET(data[5]); firstoffset <<= 8; firstoffset += GETJOCTET(data[4]); } if (firstoffset > length - 2) return; /* check end of data segment */ /* Get the number of directory entries contained in this IFD */ if (is_motorola) { number_of_tags = GETJOCTET(data[firstoffset]); number_of_tags <<= 8; number_of_tags += GETJOCTET(data[firstoffset+1]); } else { number_of_tags = GETJOCTET(data[firstoffset+1]); number_of_tags <<= 8; number_of_tags += GETJOCTET(data[firstoffset]); } if (number_of_tags == 0) return; firstoffset += 2; /* Search for ExifSubIFD offset Tag in IFD0 */ for (;;) { if (firstoffset > length - 12) return; /* check end of data segment */ /* Get Tag number */ if (is_motorola) { tagnum = GETJOCTET(data[firstoffset]); tagnum <<= 8; tagnum += GETJOCTET(data[firstoffset+1]); } else { tagnum = GETJOCTET(data[firstoffset+1]); tagnum <<= 8; tagnum += GETJOCTET(data[firstoffset]); } if (tagnum == 0x8769) break; /* found ExifSubIFD offset Tag */ if (--number_of_tags == 0) return; firstoffset += 12; } /* Get the ExifSubIFD offset */ if (is_motorola) { if (GETJOCTET(data[firstoffset+8]) != 0) return; if (GETJOCTET(data[firstoffset+9]) != 0) return; offset = GETJOCTET(data[firstoffset+10]); offset <<= 8; offset += GETJOCTET(data[firstoffset+11]); } else { if (GETJOCTET(data[firstoffset+11]) != 0) return; if (GETJOCTET(data[firstoffset+10]) != 0) return; offset = GETJOCTET(data[firstoffset+9]); offset <<= 8; offset += GETJOCTET(data[firstoffset+8]); } if (offset > length - 2) return; /* check end of data segment */ /* Get the number of directory entries contained in this SubIFD */ if (is_motorola) { number_of_tags = GETJOCTET(data[offset]); number_of_tags <<= 8; number_of_tags += GETJOCTET(data[offset+1]); } else { number_of_tags = GETJOCTET(data[offset+1]); number_of_tags <<= 8; number_of_tags += GETJOCTET(data[offset]); } if (number_of_tags < 2) return; offset += 2; /* Search for ExifImageWidth and ExifImageHeight Tags in this SubIFD */ do { if (offset > length - 12) return; /* check end of data segment */ /* Get Tag number */ if (is_motorola) { tagnum = GETJOCTET(data[offset]); tagnum <<= 8; tagnum += GETJOCTET(data[offset+1]); } else { tagnum = GETJOCTET(data[offset+1]); tagnum <<= 8; tagnum += GETJOCTET(data[offset]); } if (tagnum == 0xA002 || tagnum == 0xA003) { if (tagnum == 0xA002) new_value = new_width; /* ExifImageWidth Tag */ else new_value = new_height; /* ExifImageHeight Tag */ if (is_motorola) { data[offset+2] = 0; /* Format = unsigned long (4 octets) */ data[offset+3] = 4; data[offset+4] = 0; /* Number Of Components = 1 */ data[offset+5] = 0; data[offset+6] = 0; data[offset+7] = 1; data[offset+8] = 0; data[offset+9] = 0; data[offset+10] = (JOCTET)((new_value >> 8) & 0xFF); data[offset+11] = (JOCTET)(new_value & 0xFF); } else { data[offset+2] = 4; /* Format = unsigned long (4 octets) */ data[offset+3] = 0; data[offset+4] = 1; /* Number Of Components = 1 */ data[offset+5] = 0; data[offset+6] = 0; data[offset+7] = 0; data[offset+8] = (JOCTET)(new_value & 0xFF); data[offset+9] = (JOCTET)((new_value >> 8) & 0xFF); data[offset+10] = 0; data[offset+11] = 0; } } offset += 12; } while (--number_of_tags);}/* 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) { /* First, ensure we have YCbCr or grayscale data, and that the source's * Y channel is full resolution. (No reasonable person would make Y * be less than full resolution, so actually coping with that case * isn't worth extra code space. But we check it to avoid crashing.) */ if (((dstinfo->jpeg_color_space == JCS_YCbCr && dstinfo->num_components == 3) || (dstinfo->jpeg_color_space == JCS_GRAYSCALE && dstinfo->num_components == 1)) && srcinfo->comp_info[0].h_samp_factor == srcinfo->max_h_samp_factor && srcinfo->comp_info[0].v_samp_factor == srcinfo->max_v_samp_factor) { /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed * properly. Among other things, it sets the target h_samp_factor & * v_samp_factor to 1, which typically won't match the source. * We have to preserve the source's quantization table number, however. */ 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); } } else if (info->num_components == 1) { /* For a single-component source, we force the destination sampling factors * to 1x1, with or without force_grayscale. This is useful because some * decoders choke on grayscale images with other sampling factors. */ dstinfo->comp_info[0].h_samp_factor = 1; dstinfo->comp_info[0].v_samp_factor = 1; } /* Correct the destination's image dimensions as necessary * for crop and rotate/flip operations. */ dstinfo->image_width = info->output_width; dstinfo->image_height = info->output_height; /* Transpose destination image parameters */ switch (info->transform) { case JXFORM_TRANSPOSE: case JXFORM_TRANSVERSE: case JXFORM_ROT_90: case JXFORM_ROT_270: transpose_critical_parameters(dstinfo); break; } /* Adjust Exif properties */ if (srcinfo->marker_list != NULL && srcinfo->marker_list->marker == JPEG_APP0+1 && srcinfo->marker_list->data_length >= 6 && GETJOCTET(srcinfo->marker_list->data[0]) == 0x45 && GETJOCTET(srcinfo->marker_list->data[1]) == 0x78 && GETJOCTET(srcinfo->marker_list->data[2]) == 0x69 && GETJOCTET(srcinfo->marker_list->data[3]) == 0x66 && GETJOCTET(srcinfo->marker_list->data[4]) == 0 && GETJOCTET(srcinfo->marker_list->data[5]) == 0) { /* Suppress output of JFIF marker */ dstinfo->write_JFIF_header = FALSE; /* Adjust Exif image parameters */ if (dstinfo->image_width != srcinfo->image_width || dstinfo->image_height != srcinfo->image_height) /* Align data segment to start of TIFF structure for parsing */ adjust_exif_parameters(srcinfo->marker_list->data + 6, srcinfo->marker_list->data_length - 6, dstinfo->image_width, dstinfo->image_height); } /* 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_transform (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; /* Note: conditions tested here should match those in switch statement * in jtransform_request_workspace() */ switch (info->transform) { case JXFORM_NONE: if (info->x_crop_offset != 0 || info->y_crop_offset != 0) do_crop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); break; case JXFORM_FLIP_H: if (info->y_crop_offset != 0) do_flip_h(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); else do_flip_h_no_crop(srcinfo, dstinfo, info->x_crop_offset, src_coef_arrays); break; case JXFORM_FLIP_V: do_flip_v(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); break; case JXFORM_TRANSPOSE: do_transpose(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); break; case JXFORM_TRANSVERSE: do_transverse(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); break; case JXFORM_ROT_90: do_rot_90(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); break; case JXFORM_ROT_180: do_rot_180(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, src_coef_arrays, dst_coef_arrays); break; case JXFORM_ROT_270: do_rot_270(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset, 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 }}
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