1/* 2 * Targa (.tga) image encoder 3 * Copyright (c) 2007 Bobby Bingham 4 * 5 * This file is part of Libav. 6 * 7 * Libav 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 * Libav 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 Libav; 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 "libavutil/pixdesc.h" 24#include "avcodec.h" 25#include "rle.h" 26#include "targa.h" 27 28typedef struct TargaContext { 29 AVFrame picture; 30} TargaContext; 31 32/** 33 * RLE compress the image, with maximum size of out_size 34 * @param outbuf Output buffer 35 * @param out_size Maximum output size 36 * @param pic Image to compress 37 * @param bpp Bytes per pixel 38 * @param w Image width 39 * @param h Image height 40 * @return Size of output in bytes, or -1 if larger than out_size 41 */ 42static int targa_encode_rle(uint8_t *outbuf, int out_size, AVFrame *pic, 43 int bpp, int w, int h) 44{ 45 int y,ret; 46 uint8_t *out; 47 48 out = outbuf; 49 50 for(y = 0; y < h; y ++) { 51 ret = ff_rle_encode(out, out_size, pic->data[0] + pic->linesize[0] * y, bpp, w, 0x7f, 0, -1, 0); 52 if(ret == -1){ 53 return -1; 54 } 55 out+= ret; 56 out_size -= ret; 57 } 58 59 return out - outbuf; 60} 61 62static int targa_encode_normal(uint8_t *outbuf, AVFrame *pic, int bpp, int w, int h) 63{ 64 int i, n = bpp * w; 65 uint8_t *out = outbuf; 66 uint8_t *ptr = pic->data[0]; 67 68 for(i=0; i < h; i++) { 69 memcpy(out, ptr, n); 70 out += n; 71 ptr += pic->linesize[0]; 72 } 73 74 return out - outbuf; 75} 76 77static int targa_encode_frame(AVCodecContext *avctx, 78 unsigned char *outbuf, 79 int buf_size, void *data){ 80 AVFrame *p = data; 81 int bpp, picsize, datasize = -1; 82 uint8_t *out; 83 84 if(avctx->width > 0xffff || avctx->height > 0xffff) { 85 av_log(avctx, AV_LOG_ERROR, "image dimensions too large\n"); 86 return AVERROR(EINVAL); 87 } 88 picsize = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height); 89 if(buf_size < picsize + 45) { 90 av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n"); 91 return AVERROR(EINVAL); 92 } 93 94 p->pict_type= AV_PICTURE_TYPE_I; 95 p->key_frame= 1; 96 97 /* zero out the header and only set applicable fields */ 98 memset(outbuf, 0, 12); 99 AV_WL16(outbuf+12, avctx->width); 100 AV_WL16(outbuf+14, avctx->height); 101 /* image descriptor byte: origin is always top-left, bits 0-3 specify alpha */ 102 outbuf[17] = 0x20 | (avctx->pix_fmt == PIX_FMT_BGRA ? 8 : 0); 103 104 switch(avctx->pix_fmt) { 105 case PIX_FMT_GRAY8: 106 outbuf[2] = TGA_BW; /* uncompressed grayscale image */ 107 outbuf[16] = 8; /* bpp */ 108 break; 109 case PIX_FMT_RGB555LE: 110 outbuf[2] = TGA_RGB; /* uncompresses true-color image */ 111 outbuf[16] = 16; /* bpp */ 112 break; 113 case PIX_FMT_BGR24: 114 outbuf[2] = TGA_RGB; /* uncompressed true-color image */ 115 outbuf[16] = 24; /* bpp */ 116 break; 117 case PIX_FMT_BGRA: 118 outbuf[2] = TGA_RGB; /* uncompressed true-color image */ 119 outbuf[16] = 32; /* bpp */ 120 break; 121 default: 122 av_log(avctx, AV_LOG_ERROR, "Pixel format '%s' not supported.\n", 123 av_get_pix_fmt_name(avctx->pix_fmt)); 124 return AVERROR(EINVAL); 125 } 126 bpp = outbuf[16] >> 3; 127 128 out = outbuf + 18; /* skip past the header we just output */ 129 130 /* try RLE compression */ 131 if (avctx->coder_type != FF_CODER_TYPE_RAW) 132 datasize = targa_encode_rle(out, picsize, p, bpp, avctx->width, avctx->height); 133 134 /* if that worked well, mark the picture as RLE compressed */ 135 if(datasize >= 0) 136 outbuf[2] |= 8; 137 138 /* if RLE didn't make it smaller, go back to no compression */ 139 else datasize = targa_encode_normal(out, p, bpp, avctx->width, avctx->height); 140 141 out += datasize; 142 143 /* The standard recommends including this section, even if we don't use 144 * any of the features it affords. TODO: take advantage of the pixel 145 * aspect ratio and encoder ID fields available? */ 146 memcpy(out, "\0\0\0\0\0\0\0\0TRUEVISION-XFILE.", 26); 147 148 return out + 26 - outbuf; 149} 150 151static av_cold int targa_encode_init(AVCodecContext *avctx) 152{ 153 TargaContext *s = avctx->priv_data; 154 155 avcodec_get_frame_defaults(&s->picture); 156 s->picture.key_frame= 1; 157 avctx->coded_frame= &s->picture; 158 159 return 0; 160} 161 162AVCodec ff_targa_encoder = { 163 .name = "targa", 164 .type = AVMEDIA_TYPE_VIDEO, 165 .id = CODEC_ID_TARGA, 166 .priv_data_size = sizeof(TargaContext), 167 .init = targa_encode_init, 168 .encode = targa_encode_frame, 169 .pix_fmts= (const enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_BGRA, PIX_FMT_RGB555LE, PIX_FMT_GRAY8, PIX_FMT_NONE}, 170 .long_name= NULL_IF_CONFIG_SMALL("Truevision Targa image"), 171}; 172