blob: 02ad1e116540edadcec7a30ae1fb5ce461b5b026
1 | /* |
2 | * SGI image decoder |
3 | * Todd Kirby <doubleshot@pacbell.net> |
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/imgutils.h" |
23 | #include "libavutil/avassert.h" |
24 | #include "avcodec.h" |
25 | #include "bytestream.h" |
26 | #include "internal.h" |
27 | #include "sgi.h" |
28 | |
29 | typedef struct SgiState { |
30 | AVCodecContext *avctx; |
31 | unsigned int width; |
32 | unsigned int height; |
33 | unsigned int depth; |
34 | unsigned int bytes_per_channel; |
35 | int linesize; |
36 | GetByteContext g; |
37 | } SgiState; |
38 | |
39 | /** |
40 | * Expand an RLE row into a channel. |
41 | * @param s the current image state |
42 | * @param out_buf Points to one line after the output buffer. |
43 | * @param len length of out_buf in bytes |
44 | * @param pixelstride pixel stride of input buffer |
45 | * @return size of output in bytes, else return error code. |
46 | */ |
47 | static int expand_rle_row8(SgiState *s, uint8_t *out_buf, |
48 | int len, int pixelstride) |
49 | { |
50 | unsigned char pixel, count; |
51 | unsigned char *orig = out_buf; |
52 | uint8_t *out_end = out_buf + len; |
53 | |
54 | while (out_buf < out_end) { |
55 | if (bytestream2_get_bytes_left(&s->g) < 1) |
56 | return AVERROR_INVALIDDATA; |
57 | pixel = bytestream2_get_byteu(&s->g); |
58 | if (!(count = (pixel & 0x7f))) { |
59 | break; |
60 | } |
61 | |
62 | /* Check for buffer overflow. */ |
63 | if (out_end - out_buf <= pixelstride * (count - 1)) { |
64 | av_log(s->avctx, AV_LOG_ERROR, "Invalid pixel count.\n"); |
65 | return AVERROR_INVALIDDATA; |
66 | } |
67 | |
68 | if (pixel & 0x80) { |
69 | while (count--) { |
70 | *out_buf = bytestream2_get_byte(&s->g); |
71 | out_buf += pixelstride; |
72 | } |
73 | } else { |
74 | pixel = bytestream2_get_byte(&s->g); |
75 | |
76 | while (count--) { |
77 | *out_buf = pixel; |
78 | out_buf += pixelstride; |
79 | } |
80 | } |
81 | } |
82 | return (out_buf - orig) / pixelstride; |
83 | } |
84 | |
85 | static int expand_rle_row16(SgiState *s, uint16_t *out_buf, |
86 | int len, int pixelstride) |
87 | { |
88 | unsigned short pixel; |
89 | unsigned char count; |
90 | unsigned short *orig = out_buf; |
91 | uint16_t *out_end = out_buf + len; |
92 | |
93 | while (out_buf < out_end) { |
94 | if (bytestream2_get_bytes_left(&s->g) < 2) |
95 | return AVERROR_INVALIDDATA; |
96 | pixel = bytestream2_get_be16u(&s->g); |
97 | if (!(count = (pixel & 0x7f))) |
98 | break; |
99 | |
100 | /* Check for buffer overflow. */ |
101 | if (out_end - out_buf <= pixelstride * (count - 1)) { |
102 | av_log(s->avctx, AV_LOG_ERROR, "Invalid pixel count.\n"); |
103 | return AVERROR_INVALIDDATA; |
104 | } |
105 | |
106 | if (pixel & 0x80) { |
107 | while (count--) { |
108 | pixel = bytestream2_get_ne16(&s->g); |
109 | AV_WN16A(out_buf, pixel); |
110 | out_buf += pixelstride; |
111 | } |
112 | } else { |
113 | pixel = bytestream2_get_ne16(&s->g); |
114 | |
115 | while (count--) { |
116 | AV_WN16A(out_buf, pixel); |
117 | out_buf += pixelstride; |
118 | } |
119 | } |
120 | } |
121 | return (out_buf - orig) / pixelstride; |
122 | } |
123 | |
124 | |
125 | /** |
126 | * Read a run length encoded SGI image. |
127 | * @param out_buf output buffer |
128 | * @param s the current image state |
129 | * @return 0 if no error, else return error code. |
130 | */ |
131 | static int read_rle_sgi(uint8_t *out_buf, SgiState *s) |
132 | { |
133 | uint8_t *dest_row; |
134 | unsigned int len = s->height * s->depth * 4; |
135 | GetByteContext g_table = s->g; |
136 | unsigned int y, z; |
137 | unsigned int start_offset; |
138 | int linesize, ret; |
139 | |
140 | /* size of RLE offset and length tables */ |
141 | if (len * 2 > bytestream2_get_bytes_left(&s->g)) { |
142 | return AVERROR_INVALIDDATA; |
143 | } |
144 | |
145 | for (z = 0; z < s->depth; z++) { |
146 | dest_row = out_buf; |
147 | for (y = 0; y < s->height; y++) { |
148 | linesize = s->width * s->depth; |
149 | dest_row -= s->linesize; |
150 | start_offset = bytestream2_get_be32(&g_table); |
151 | bytestream2_seek(&s->g, start_offset, SEEK_SET); |
152 | if (s->bytes_per_channel == 1) |
153 | ret = expand_rle_row8(s, dest_row + z, linesize, s->depth); |
154 | else |
155 | ret = expand_rle_row16(s, (uint16_t *)dest_row + z, linesize, s->depth); |
156 | if (ret != s->width) |
157 | return AVERROR_INVALIDDATA; |
158 | } |
159 | } |
160 | return 0; |
161 | } |
162 | |
163 | /** |
164 | * Read an uncompressed SGI image. |
165 | * @param out_buf output buffer |
166 | * @param s the current image state |
167 | * @return 0 if read success, else return error code. |
168 | */ |
169 | static int read_uncompressed_sgi(unsigned char *out_buf, SgiState *s) |
170 | { |
171 | int x, y, z; |
172 | unsigned int offset = s->height * s->width * s->bytes_per_channel; |
173 | GetByteContext gp[4]; |
174 | uint8_t *out_end; |
175 | |
176 | /* Test buffer size. */ |
177 | if (offset * s->depth > bytestream2_get_bytes_left(&s->g)) |
178 | return AVERROR_INVALIDDATA; |
179 | |
180 | /* Create a reader for each plane */ |
181 | for (z = 0; z < s->depth; z++) { |
182 | gp[z] = s->g; |
183 | bytestream2_skip(&gp[z], z * offset); |
184 | } |
185 | |
186 | for (y = s->height - 1; y >= 0; y--) { |
187 | out_end = out_buf + (y * s->linesize); |
188 | if (s->bytes_per_channel == 1) { |
189 | for (x = s->width; x > 0; x--) |
190 | for (z = 0; z < s->depth; z++) |
191 | *out_end++ = bytestream2_get_byteu(&gp[z]); |
192 | } else { |
193 | uint16_t *out16 = (uint16_t *)out_end; |
194 | for (x = s->width; x > 0; x--) |
195 | for (z = 0; z < s->depth; z++) |
196 | *out16++ = bytestream2_get_ne16u(&gp[z]); |
197 | } |
198 | } |
199 | return 0; |
200 | } |
201 | |
202 | static int decode_frame(AVCodecContext *avctx, |
203 | void *data, int *got_frame, |
204 | AVPacket *avpkt) |
205 | { |
206 | SgiState *s = avctx->priv_data; |
207 | AVFrame *p = data; |
208 | unsigned int dimension, rle; |
209 | int ret = 0; |
210 | uint8_t *out_buf, *out_end; |
211 | |
212 | bytestream2_init(&s->g, avpkt->data, avpkt->size); |
213 | if (bytestream2_get_bytes_left(&s->g) < SGI_HEADER_SIZE) { |
214 | av_log(avctx, AV_LOG_ERROR, "buf_size too small (%d)\n", avpkt->size); |
215 | return AVERROR_INVALIDDATA; |
216 | } |
217 | |
218 | /* Test for SGI magic. */ |
219 | if (bytestream2_get_be16u(&s->g) != SGI_MAGIC) { |
220 | av_log(avctx, AV_LOG_ERROR, "bad magic number\n"); |
221 | return AVERROR_INVALIDDATA; |
222 | } |
223 | |
224 | rle = bytestream2_get_byteu(&s->g); |
225 | s->bytes_per_channel = bytestream2_get_byteu(&s->g); |
226 | dimension = bytestream2_get_be16u(&s->g); |
227 | s->width = bytestream2_get_be16u(&s->g); |
228 | s->height = bytestream2_get_be16u(&s->g); |
229 | s->depth = bytestream2_get_be16u(&s->g); |
230 | |
231 | if (s->bytes_per_channel != 1 && s->bytes_per_channel != 2) { |
232 | av_log(avctx, AV_LOG_ERROR, "wrong channel number\n"); |
233 | return AVERROR_INVALIDDATA; |
234 | } |
235 | |
236 | /* Check for supported image dimensions. */ |
237 | if (dimension != 2 && dimension != 3) { |
238 | av_log(avctx, AV_LOG_ERROR, "wrong dimension number\n"); |
239 | return AVERROR_INVALIDDATA; |
240 | } |
241 | |
242 | if (s->depth == SGI_GRAYSCALE) { |
243 | avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_GRAY16BE : AV_PIX_FMT_GRAY8; |
244 | } else if (s->depth == SGI_RGB) { |
245 | avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGB48BE : AV_PIX_FMT_RGB24; |
246 | } else if (s->depth == SGI_RGBA) { |
247 | avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGBA64BE : AV_PIX_FMT_RGBA; |
248 | } else { |
249 | av_log(avctx, AV_LOG_ERROR, "wrong picture format\n"); |
250 | return AVERROR_INVALIDDATA; |
251 | } |
252 | |
253 | ret = ff_set_dimensions(avctx, s->width, s->height); |
254 | if (ret < 0) |
255 | return ret; |
256 | |
257 | if ((ret = ff_get_buffer(avctx, p, 0)) < 0) |
258 | return ret; |
259 | |
260 | p->pict_type = AV_PICTURE_TYPE_I; |
261 | p->key_frame = 1; |
262 | out_buf = p->data[0]; |
263 | |
264 | out_end = out_buf + p->linesize[0] * s->height; |
265 | |
266 | s->linesize = p->linesize[0]; |
267 | |
268 | /* Skip header. */ |
269 | bytestream2_seek(&s->g, SGI_HEADER_SIZE, SEEK_SET); |
270 | if (rle) { |
271 | ret = read_rle_sgi(out_end, s); |
272 | } else { |
273 | ret = read_uncompressed_sgi(out_buf, s); |
274 | } |
275 | if (ret) |
276 | return ret; |
277 | |
278 | *got_frame = 1; |
279 | return avpkt->size; |
280 | } |
281 | |
282 | static av_cold int sgi_decode_init(AVCodecContext *avctx) |
283 | { |
284 | SgiState *s = avctx->priv_data; |
285 | |
286 | s->avctx = avctx; |
287 | |
288 | return 0; |
289 | } |
290 | |
291 | AVCodec ff_sgi_decoder = { |
292 | .name = "sgi", |
293 | .long_name = NULL_IF_CONFIG_SMALL("SGI image"), |
294 | .type = AVMEDIA_TYPE_VIDEO, |
295 | .id = AV_CODEC_ID_SGI, |
296 | .priv_data_size = sizeof(SgiState), |
297 | .decode = decode_frame, |
298 | .init = sgi_decode_init, |
299 | .capabilities = AV_CODEC_CAP_DR1, |
300 | }; |
301 |