| /* |
| * wrtarga.c |
| * |
| * This file was part of the Independent JPEG Group's software: |
| * Copyright (C) 1991-1996, Thomas G. Lane. |
| * libjpeg-turbo Modifications: |
| * Copyright (C) 2017, 2019, 2022, D. R. Commander. |
| * For conditions of distribution and use, see the accompanying README.ijg |
| * file. |
| * |
| * This file contains routines to write output images in Targa format. |
| * |
| * These routines may need modification for non-Unix environments or |
| * specialized applications. As they stand, they assume output to |
| * an ordinary stdio stream. |
| * |
| * Based on code contributed by Lee Daniel Crocker. |
| */ |
| |
| #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */ |
| |
| #ifdef TARGA_SUPPORTED |
| |
| |
| /* |
| * To support 12-bit JPEG data, we'd have to scale output down to 8 bits. |
| * This is not yet implemented. |
| */ |
| |
| #if BITS_IN_JSAMPLE != 8 |
| Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */ |
| #endif |
| |
| |
| /* Private version of data destination object */ |
| |
| typedef struct { |
| struct djpeg_dest_struct pub; /* public fields */ |
| |
| char *iobuffer; /* physical I/O buffer */ |
| JDIMENSION buffer_width; /* width of one row */ |
| } tga_dest_struct; |
| |
| typedef tga_dest_struct *tga_dest_ptr; |
| |
| |
| LOCAL(void) |
| write_header(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, int num_colors) |
| /* Create and write a Targa header */ |
| { |
| char targaheader[18]; |
| |
| /* Set unused fields of header to 0 */ |
| memset(targaheader, 0, sizeof(targaheader)); |
| |
| if (num_colors > 0) { |
| targaheader[1] = 1; /* color map type 1 */ |
| targaheader[5] = (char)(num_colors & 0xFF); |
| targaheader[6] = (char)(num_colors >> 8); |
| targaheader[7] = 24; /* 24 bits per cmap entry */ |
| } |
| |
| targaheader[12] = (char)(cinfo->output_width & 0xFF); |
| targaheader[13] = (char)(cinfo->output_width >> 8); |
| targaheader[14] = (char)(cinfo->output_height & 0xFF); |
| targaheader[15] = (char)(cinfo->output_height >> 8); |
| targaheader[17] = 0x20; /* Top-down, non-interlaced */ |
| |
| if (cinfo->out_color_space == JCS_GRAYSCALE) { |
| targaheader[2] = 3; /* image type = uncompressed grayscale */ |
| targaheader[16] = 8; /* bits per pixel */ |
| } else { /* must be RGB */ |
| if (num_colors > 0) { |
| targaheader[2] = 1; /* image type = colormapped RGB */ |
| targaheader[16] = 8; |
| } else { |
| targaheader[2] = 2; /* image type = uncompressed RGB */ |
| targaheader[16] = 24; |
| } |
| } |
| |
| if (fwrite(targaheader, 1, 18, dinfo->output_file) != (size_t)18) |
| ERREXIT(cinfo, JERR_FILE_WRITE); |
| } |
| |
| |
| /* |
| * Write some pixel data. |
| * In this module rows_supplied will always be 1. |
| */ |
| |
| METHODDEF(void) |
| put_pixel_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, |
| JDIMENSION rows_supplied) |
| /* used for unquantized full-color output */ |
| { |
| tga_dest_ptr dest = (tga_dest_ptr)dinfo; |
| register JSAMPROW inptr; |
| register char *outptr; |
| register JDIMENSION col; |
| |
| inptr = dest->pub.buffer[0]; |
| outptr = dest->iobuffer; |
| for (col = cinfo->output_width; col > 0; col--) { |
| outptr[0] = inptr[2]; /* RGB to BGR order */ |
| outptr[1] = inptr[1]; |
| outptr[2] = inptr[0]; |
| inptr += 3, outptr += 3; |
| } |
| fwrite(dest->iobuffer, 1, dest->buffer_width, dest->pub.output_file); |
| } |
| |
| METHODDEF(void) |
| put_gray_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, |
| JDIMENSION rows_supplied) |
| /* used for grayscale OR quantized color output */ |
| { |
| tga_dest_ptr dest = (tga_dest_ptr)dinfo; |
| register JSAMPROW inptr; |
| register char *outptr; |
| |
| inptr = dest->pub.buffer[0]; |
| outptr = dest->iobuffer; |
| memcpy(outptr, inptr, cinfo->output_width); |
| fwrite(dest->iobuffer, 1, dest->buffer_width, dest->pub.output_file); |
| } |
| |
| |
| /* |
| * Write some demapped pixel data when color quantization is in effect. |
| * For Targa, this is only applied to grayscale data. |
| */ |
| |
| METHODDEF(void) |
| put_demapped_gray(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, |
| JDIMENSION rows_supplied) |
| { |
| tga_dest_ptr dest = (tga_dest_ptr)dinfo; |
| register JSAMPROW inptr; |
| register char *outptr; |
| register JSAMPROW color_map0 = cinfo->colormap[0]; |
| register JDIMENSION col; |
| |
| inptr = dest->pub.buffer[0]; |
| outptr = dest->iobuffer; |
| for (col = cinfo->output_width; col > 0; col--) { |
| *outptr++ = color_map0[*inptr++]; |
| } |
| fwrite(dest->iobuffer, 1, dest->buffer_width, dest->pub.output_file); |
| } |
| |
| |
| /* |
| * Startup: write the file header. |
| */ |
| |
| METHODDEF(void) |
| start_output_tga(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) |
| { |
| tga_dest_ptr dest = (tga_dest_ptr)dinfo; |
| int num_colors, i; |
| FILE *outfile; |
| |
| if (cinfo->out_color_space == JCS_GRAYSCALE) { |
| /* Targa doesn't have a mapped grayscale format, so we will */ |
| /* demap quantized gray output. Never emit a colormap. */ |
| write_header(cinfo, dinfo, 0); |
| if (cinfo->quantize_colors) |
| dest->pub.put_pixel_rows = put_demapped_gray; |
| else |
| dest->pub.put_pixel_rows = put_gray_rows; |
| } else if (cinfo->out_color_space == JCS_RGB) { |
| if (cinfo->quantize_colors) { |
| /* We only support 8-bit colormap indexes, so only 256 colors */ |
| num_colors = cinfo->actual_number_of_colors; |
| if (num_colors > 256) |
| ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, num_colors); |
| write_header(cinfo, dinfo, num_colors); |
| /* Write the colormap. Note Targa uses BGR byte order */ |
| outfile = dest->pub.output_file; |
| for (i = 0; i < num_colors; i++) { |
| putc(cinfo->colormap[2][i], outfile); |
| putc(cinfo->colormap[1][i], outfile); |
| putc(cinfo->colormap[0][i], outfile); |
| } |
| dest->pub.put_pixel_rows = put_gray_rows; |
| } else { |
| write_header(cinfo, dinfo, 0); |
| dest->pub.put_pixel_rows = put_pixel_rows; |
| } |
| } else { |
| ERREXIT(cinfo, JERR_TGA_COLORSPACE); |
| } |
| } |
| |
| |
| /* |
| * Finish up at the end of the file. |
| */ |
| |
| METHODDEF(void) |
| finish_output_tga(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) |
| { |
| /* Make sure we wrote the output file OK */ |
| fflush(dinfo->output_file); |
| if (ferror(dinfo->output_file)) |
| ERREXIT(cinfo, JERR_FILE_WRITE); |
| } |
| |
| |
| /* |
| * Re-calculate buffer dimensions based on output dimensions. |
| */ |
| |
| METHODDEF(void) |
| calc_buffer_dimensions_tga(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) |
| { |
| tga_dest_ptr dest = (tga_dest_ptr)dinfo; |
| |
| dest->buffer_width = cinfo->output_width * cinfo->output_components; |
| } |
| |
| |
| /* |
| * The module selection routine for Targa format output. |
| */ |
| |
| GLOBAL(djpeg_dest_ptr) |
| jinit_write_targa(j_decompress_ptr cinfo) |
| { |
| tga_dest_ptr dest; |
| |
| if (cinfo->data_precision != 8) |
| ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); |
| |
| /* Create module interface object, fill in method pointers */ |
| dest = (tga_dest_ptr) |
| (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE, |
| sizeof(tga_dest_struct)); |
| dest->pub.start_output = start_output_tga; |
| dest->pub.finish_output = finish_output_tga; |
| dest->pub.calc_buffer_dimensions = calc_buffer_dimensions_tga; |
| |
| /* Calculate output image dimensions so we can allocate space */ |
| jpeg_calc_output_dimensions(cinfo); |
| |
| /* Create I/O buffer. */ |
| dest->pub.calc_buffer_dimensions(cinfo, (djpeg_dest_ptr)dest); |
| dest->iobuffer = (char *) |
| (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE, |
| (size_t)(dest->buffer_width * sizeof(char))); |
| |
| /* Create decompressor output buffer. */ |
| dest->pub.buffer = (*cinfo->mem->alloc_sarray) |
| ((j_common_ptr)cinfo, JPOOL_IMAGE, dest->buffer_width, (JDIMENSION)1); |
| dest->pub.buffer_height = 1; |
| |
| return (djpeg_dest_ptr)dest; |
| } |
| |
| #endif /* TARGA_SUPPORTED */ |