1/*
2 * Targa (.tga) image decoder
3 * Copyright (c) 2006 Konstantin Shishkov
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
25enum TargaCompr{
26    TGA_NODATA = 0, // no image data
27    TGA_PAL    = 1, // palettized
28    TGA_RGB    = 2, // true-color
29    TGA_BW     = 3, // black & white or grayscale
30    TGA_RLE    = 8, // flag pointing that data is RLE-coded
31};
32
33typedef struct TargaContext {
34    AVFrame picture;
35
36    int width, height;
37    int bpp;
38    int color_type;
39    int compression_type;
40} TargaContext;
41
42static void targa_decode_rle(AVCodecContext *avctx, TargaContext *s, const uint8_t *src, uint8_t *dst, int w, int h, int stride, int bpp)
43{
44    int i, x, y;
45    int depth = (bpp + 1) >> 3;
46    int type, count;
47    int diff;
48
49    diff = stride - w * depth;
50    x = y = 0;
51    while(y < h){
52        type = *src++;
53        count = (type & 0x7F) + 1;
54        type &= 0x80;
55        if((x + count > w) && (x + count + 1 > (h - y) * w)){
56            av_log(avctx, AV_LOG_ERROR, "Packet went out of bounds: position (%i,%i) size %i\n", x, y, count);
57            return;
58        }
59        for(i = 0; i < count; i++){
60            switch(depth){
61            case 1:
62                *dst = *src;
63                break;
64            case 2:
65                *((uint16_t*)dst) = AV_RL16(src);
66                break;
67            case 3:
68                dst[0] = src[0];
69                dst[1] = src[1];
70                dst[2] = src[2];
71                break;
72            case 4:
73                *((uint32_t*)dst) = AV_RL32(src);
74                break;
75            }
76            dst += depth;
77            if(!type)
78                src += depth;
79
80            x++;
81            if(x == w){
82                x = 0;
83                y++;
84                dst += diff;
85            }
86        }
87        if(type)
88            src += depth;
89    }
90}
91
92static int decode_frame(AVCodecContext *avctx,
93                        void *data, int *data_size,
94                        AVPacket *avpkt)
95{
96    const uint8_t *buf = avpkt->data;
97    int buf_size = avpkt->size;
98    TargaContext * const s = avctx->priv_data;
99    AVFrame *picture = data;
100    AVFrame * const p= (AVFrame*)&s->picture;
101    uint8_t *dst;
102    int stride;
103    int idlen, pal, compr, x, y, w, h, bpp, flags;
104    int first_clr, colors, csize;
105
106    /* parse image header */
107    idlen = *buf++;
108    pal = *buf++;
109    compr = *buf++;
110    first_clr = AV_RL16(buf); buf += 2;
111    colors = AV_RL16(buf); buf += 2;
112    csize = *buf++;
113    x = AV_RL16(buf); buf += 2;
114    y = AV_RL16(buf); buf += 2;
115    w = AV_RL16(buf); buf += 2;
116    h = AV_RL16(buf); buf += 2;
117    bpp = *buf++;
118    flags = *buf++;
119    //skip identifier if any
120    buf += idlen;
121    s->bpp = bpp;
122    s->width = w;
123    s->height = h;
124    switch(s->bpp){
125    case 8:
126        avctx->pix_fmt = ((compr & (~TGA_RLE)) == TGA_BW) ? PIX_FMT_GRAY8 : PIX_FMT_PAL8;
127        break;
128    case 15:
129        avctx->pix_fmt = PIX_FMT_RGB555;
130        break;
131    case 16:
132        avctx->pix_fmt = PIX_FMT_RGB555;
133        break;
134    case 24:
135        avctx->pix_fmt = PIX_FMT_BGR24;
136        break;
137    case 32:
138        avctx->pix_fmt = PIX_FMT_RGB32;
139        break;
140    default:
141        av_log(avctx, AV_LOG_ERROR, "Bit depth %i is not supported\n", s->bpp);
142        return -1;
143    }
144
145    if(s->picture.data[0])
146        avctx->release_buffer(avctx, &s->picture);
147
148    if(avcodec_check_dimensions(avctx, w, h))
149        return -1;
150    if(w != avctx->width || h != avctx->height)
151        avcodec_set_dimensions(avctx, w, h);
152    if(avctx->get_buffer(avctx, p) < 0){
153        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
154        return -1;
155    }
156    if(flags & 0x20){
157        dst = p->data[0];
158        stride = p->linesize[0];
159    }else{ //image is upside-down
160        dst = p->data[0] + p->linesize[0] * (h - 1);
161        stride = -p->linesize[0];
162    }
163
164    if(avctx->pix_fmt == PIX_FMT_PAL8 && avctx->palctrl){
165        memcpy(p->data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
166        if(avctx->palctrl->palette_changed){
167            p->palette_has_changed = 1;
168            avctx->palctrl->palette_changed = 0;
169        }
170    }
171    if(colors){
172        if((colors + first_clr) > 256){
173            av_log(avctx, AV_LOG_ERROR, "Incorrect palette: %i colors with offset %i\n", colors, first_clr);
174            return -1;
175        }
176        if(csize != 24){
177            av_log(avctx, AV_LOG_ERROR, "Palette entry size %i bits is not supported\n", csize);
178            return -1;
179        }
180        if(avctx->pix_fmt != PIX_FMT_PAL8)//should not occur but skip palette anyway
181            buf += colors * ((csize + 1) >> 3);
182        else{
183            int r, g, b, t;
184            int32_t *pal = ((int32_t*)p->data[1]) + first_clr;
185            for(t = 0; t < colors; t++){
186                r = *buf++;
187                g = *buf++;
188                b = *buf++;
189                *pal++ = (b << 16) | (g << 8) | r;
190            }
191            p->palette_has_changed = 1;
192        }
193    }
194    if((compr & (~TGA_RLE)) == TGA_NODATA)
195        memset(p->data[0], 0, p->linesize[0] * s->height);
196    else{
197        if(compr & TGA_RLE)
198            targa_decode_rle(avctx, s, buf, dst, avctx->width, avctx->height, stride, bpp);
199        else{
200            for(y = 0; y < s->height; y++){
201#if HAVE_BIGENDIAN
202                if((s->bpp + 1) >> 3 == 2){
203                    uint16_t *dst16 = (uint16_t*)dst;
204                    for(x = 0; x < s->width; x++)
205                        dst16[x] = AV_RL16(buf + x * 2);
206                }else if((s->bpp + 1) >> 3 == 4){
207                    uint32_t *dst32 = (uint32_t*)dst;
208                    for(x = 0; x < s->width; x++)
209                        dst32[x] = AV_RL32(buf + x * 4);
210                }else
211#endif
212                    memcpy(dst, buf, s->width * ((s->bpp + 1) >> 3));
213
214                dst += stride;
215                buf += s->width * ((s->bpp + 1) >> 3);
216            }
217        }
218    }
219
220    *picture= *(AVFrame*)&s->picture;
221    *data_size = sizeof(AVPicture);
222
223    return buf_size;
224}
225
226static av_cold int targa_init(AVCodecContext *avctx){
227    TargaContext *s = avctx->priv_data;
228
229    avcodec_get_frame_defaults((AVFrame*)&s->picture);
230    avctx->coded_frame= (AVFrame*)&s->picture;
231
232    return 0;
233}
234
235static av_cold int targa_end(AVCodecContext *avctx){
236    TargaContext *s = avctx->priv_data;
237
238    if(s->picture.data[0])
239        avctx->release_buffer(avctx, &s->picture);
240
241    return 0;
242}
243
244AVCodec targa_decoder = {
245    "targa",
246    AVMEDIA_TYPE_VIDEO,
247    CODEC_ID_TARGA,
248    sizeof(TargaContext),
249    targa_init,
250    NULL,
251    targa_end,
252    decode_frame,
253    CODEC_CAP_DR1,
254    NULL,
255    .long_name = NULL_IF_CONFIG_SMALL("Truevision Targa image"),
256};
257