📄 transupp.c
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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 }}
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