1/* 2 * Targa (.tga) image encoder 3 * Copyright (c) 2007 Bobby Bingham 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/intreadwrite.h" 23#include "avcodec.h" 24#include "rle.h" 25 26typedef struct TargaContext { 27 AVFrame picture; 28} TargaContext; 29 30/** 31 * RLE compress the image, with maximum size of out_size 32 * @param outbuf Output buffer 33 * @param out_size Maximum output size 34 * @param pic Image to compress 35 * @param bpp Bytes per pixel 36 * @param w Image width 37 * @param h Image height 38 * @return Size of output in bytes, or -1 if larger than out_size 39 */ 40static int targa_encode_rle(uint8_t *outbuf, int out_size, AVFrame *pic, 41 int bpp, int w, int h) 42{ 43 int y,ret; 44 uint8_t *out; 45 46 out = outbuf; 47 48 for(y = 0; y < h; y ++) { 49 ret = ff_rle_encode(out, out_size, pic->data[0] + pic->linesize[0] * y, bpp, w, 0x7f, 0, -1, 0); 50 if(ret == -1){ 51 return -1; 52 } 53 out+= ret; 54 out_size -= ret; 55 } 56 57 return out - outbuf; 58} 59 60static int targa_encode_normal(uint8_t *outbuf, AVFrame *pic, int bpp, int w, int h) 61{ 62 int i, n = bpp * w; 63 uint8_t *out = outbuf; 64 uint8_t *ptr = pic->data[0]; 65 66 for(i=0; i < h; i++) { 67 memcpy(out, ptr, n); 68 out += n; 69 ptr += pic->linesize[0]; 70 } 71 72 return out - outbuf; 73} 74 75static int targa_encode_frame(AVCodecContext *avctx, 76 unsigned char *outbuf, 77 int buf_size, void *data){ 78 AVFrame *p = data; 79 int bpp, picsize, datasize; 80 uint8_t *out; 81 82 if(avctx->width > 0xffff || avctx->height > 0xffff) { 83 av_log(avctx, AV_LOG_ERROR, "image dimensions too large\n"); 84 return -1; 85 } 86 picsize = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height); 87 if(buf_size < picsize + 45) { 88 av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n"); 89 return -1; 90 } 91 92 p->pict_type= FF_I_TYPE; 93 p->key_frame= 1; 94 95 /* zero out the header and only set applicable fields */ 96 memset(outbuf, 0, 12); 97 AV_WL16(outbuf+12, avctx->width); 98 AV_WL16(outbuf+14, avctx->height); 99 outbuf[17] = 0x20; /* origin is top-left. no alpha */ 100 101 /* TODO: support alpha channel */ 102 switch(avctx->pix_fmt) { 103 case PIX_FMT_GRAY8: 104 outbuf[2] = 3; /* uncompressed grayscale image */ 105 outbuf[16] = 8; /* bpp */ 106 break; 107 case PIX_FMT_RGB555: 108 outbuf[2] = 2; /* uncompresses true-color image */ 109 outbuf[16] = 16; /* bpp */ 110 break; 111 case PIX_FMT_BGR24: 112 outbuf[2] = 2; /* uncompressed true-color image */ 113 outbuf[16] = 24; /* bpp */ 114 break; 115 default: 116 return -1; 117 } 118 bpp = outbuf[16] >> 3; 119 120 out = outbuf + 18; /* skip past the header we just output */ 121 122 /* try RLE compression */ 123 datasize = targa_encode_rle(out, picsize, p, bpp, avctx->width, avctx->height); 124 125 /* if that worked well, mark the picture as RLE compressed */ 126 if(datasize >= 0) 127 outbuf[2] |= 8; 128 129 /* if RLE didn't make it smaller, go back to no compression */ 130 else datasize = targa_encode_normal(out, p, bpp, avctx->width, avctx->height); 131 132 out += datasize; 133 134 /* The standard recommends including this section, even if we don't use 135 * any of the features it affords. TODO: take advantage of the pixel 136 * aspect ratio and encoder ID fields available? */ 137 memcpy(out, "\0\0\0\0\0\0\0\0TRUEVISION-XFILE.", 26); 138 139 return out + 26 - outbuf; 140} 141 142static av_cold int targa_encode_init(AVCodecContext *avctx) 143{ 144 TargaContext *s = avctx->priv_data; 145 146 avcodec_get_frame_defaults(&s->picture); 147 s->picture.key_frame= 1; 148 avctx->coded_frame= &s->picture; 149 150 return 0; 151} 152 153AVCodec targa_encoder = { 154 .name = "targa", 155 .type = CODEC_TYPE_VIDEO, 156 .id = CODEC_ID_TARGA, 157 .priv_data_size = sizeof(TargaContext), 158 .init = targa_encode_init, 159 .encode = targa_encode_frame, 160 .pix_fmts= (enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_RGB555, PIX_FMT_GRAY8, PIX_FMT_NONE}, 161 .long_name= NULL_IF_CONFIG_SMALL("Truevision Targa image"), 162}; 163