1 /*
2 * innoHeim/Rsupport Screen Capture Codec
3 * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
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 /**
23 * @file
24 * innoHeim/Rsupport Screen Capture Codec decoder
25 *
26 * Fourcc: ISCC, RSCC
27 *
28 * Lossless codec, data stored in tiles, with optional deflate compression.
29 *
30 * Header contains the number of tiles in a frame with the tile coordinates,
31 * and it can be deflated or not. Similarly, pixel data comes after the header
32 * and a variable size value, and it can be deflated or just raw.
33 *
34 * Supports: PAL8, BGRA, BGR24, RGB555
35 */
36
37 #include <stdint.h>
38 #include <string.h>
39 #include <zlib.h>
40
41 #include "libavutil/imgutils.h"
42 #include "libavutil/internal.h"
43
44 #include "avcodec.h"
45 #include "bytestream.h"
46 #include "internal.h"
47
48 #define TILE_SIZE 8
49
50 typedef struct Tile {
51 int x, y;
52 int w, h;
53 } Tile;
54
55 typedef struct RsccContext {
56 GetByteContext gbc;
57 AVFrame *reference;
58 Tile *tiles;
59 unsigned int tiles_size;
60 int component_size;
61
62 uint8_t palette[AVPALETTE_SIZE];
63
64 /* zlib interaction */
65 uint8_t *inflated_buf;
66 uLongf inflated_size;
67 int valid_pixels;
68 } RsccContext;
69
rscc_init(AVCodecContext * avctx)70 static av_cold int rscc_init(AVCodecContext *avctx)
71 {
72 RsccContext *ctx = avctx->priv_data;
73
74 /* These needs to be set to estimate uncompressed buffer */
75 int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
76 if (ret < 0) {
77 av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
78 avctx->width, avctx->height);
79 return ret;
80 }
81
82 /* Allocate reference frame */
83 ctx->reference = av_frame_alloc();
84 if (!ctx->reference)
85 return AVERROR(ENOMEM);
86
87 /* Get pixel format and the size of the pixel */
88 if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
89 if (avctx->extradata && avctx->extradata_size == 4) {
90 if ((avctx->extradata[0] >> 1) & 1) {
91 avctx->pix_fmt = AV_PIX_FMT_BGRA;
92 ctx->component_size = 4;
93 } else {
94 avctx->pix_fmt = AV_PIX_FMT_BGR24;
95 ctx->component_size = 3;
96 }
97 } else {
98 avctx->pix_fmt = AV_PIX_FMT_BGRA;
99 ctx->component_size = 4;
100 }
101 } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
102 ctx->component_size = avctx->bits_per_coded_sample / 8;
103 switch (avctx->bits_per_coded_sample) {
104 case 8:
105 avctx->pix_fmt = AV_PIX_FMT_PAL8;
106 break;
107 case 16:
108 avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
109 break;
110 case 24:
111 avctx->pix_fmt = AV_PIX_FMT_BGR24;
112 break;
113 case 32:
114 avctx->pix_fmt = AV_PIX_FMT_BGR0;
115 break;
116 default:
117 av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
118 avctx->bits_per_coded_sample);
119 return AVERROR_INVALIDDATA;
120 }
121 } else {
122 avctx->pix_fmt = AV_PIX_FMT_BGR0;
123 ctx->component_size = 4;
124 av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
125 }
126
127 /* Store the value to check for keyframes */
128 ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
129
130 /* Allocate maximum size possible, a full frame */
131 ctx->inflated_buf = av_malloc(ctx->inflated_size);
132 if (!ctx->inflated_buf)
133 return AVERROR(ENOMEM);
134
135 return 0;
136 }
137
rscc_close(AVCodecContext * avctx)138 static av_cold int rscc_close(AVCodecContext *avctx)
139 {
140 RsccContext *ctx = avctx->priv_data;
141
142 av_freep(&ctx->tiles);
143 av_freep(&ctx->inflated_buf);
144 av_frame_free(&ctx->reference);
145
146 return 0;
147 }
148
rscc_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)149 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
150 int *got_frame, AVPacket *avpkt)
151 {
152 RsccContext *ctx = avctx->priv_data;
153 GetByteContext *gbc = &ctx->gbc;
154 GetByteContext tiles_gbc;
155 AVFrame *frame = data;
156 const uint8_t *pixels, *raw;
157 uint8_t *inflated_tiles = NULL;
158 int tiles_nb, packed_size, pixel_size = 0;
159 int i, ret = 0;
160
161 bytestream2_init(gbc, avpkt->data, avpkt->size);
162
163 /* Size check */
164 if (bytestream2_get_bytes_left(gbc) < 12) {
165 av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
166 return AVERROR_INVALIDDATA;
167 }
168
169 /* Read number of tiles, and allocate the array */
170 tiles_nb = bytestream2_get_le16(gbc);
171
172 if (tiles_nb == 0) {
173 av_log(avctx, AV_LOG_DEBUG, "no tiles\n");
174 return avpkt->size;
175 }
176
177 av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
178 tiles_nb * sizeof(*ctx->tiles));
179 if (!ctx->tiles) {
180 ret = AVERROR(ENOMEM);
181 goto end;
182 }
183
184 av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
185
186 /* When there are more than 5 tiles, they are packed together with
187 * a size header. When that size does not match the number of tiles
188 * times the tile size, it means it needs to be inflated as well */
189 if (tiles_nb > 5) {
190 uLongf packed_tiles_size;
191
192 if (tiles_nb < 32)
193 packed_tiles_size = bytestream2_get_byte(gbc);
194 else
195 packed_tiles_size = bytestream2_get_le16(gbc);
196
197 ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
198
199 /* If necessary, uncompress tiles, and hijack the bytestream reader */
200 if (packed_tiles_size != tiles_nb * TILE_SIZE) {
201 uLongf length = tiles_nb * TILE_SIZE;
202
203 if (bytestream2_get_bytes_left(gbc) < packed_tiles_size) {
204 ret = AVERROR_INVALIDDATA;
205 goto end;
206 }
207
208 inflated_tiles = av_malloc(length);
209 if (!inflated_tiles) {
210 ret = AVERROR(ENOMEM);
211 goto end;
212 }
213
214 ret = uncompress(inflated_tiles, &length,
215 gbc->buffer, packed_tiles_size);
216 if (ret) {
217 av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
218 ret = AVERROR_UNKNOWN;
219 goto end;
220 }
221
222 /* Skip the compressed tile section in the main byte reader,
223 * and point it to read the newly uncompressed data */
224 bytestream2_skip(gbc, packed_tiles_size);
225 bytestream2_init(&tiles_gbc, inflated_tiles, length);
226 gbc = &tiles_gbc;
227 }
228 }
229
230 /* Fill in array of tiles, keeping track of how many pixels are updated */
231 for (i = 0; i < tiles_nb; i++) {
232 ctx->tiles[i].x = bytestream2_get_le16(gbc);
233 ctx->tiles[i].w = bytestream2_get_le16(gbc);
234 ctx->tiles[i].y = bytestream2_get_le16(gbc);
235 ctx->tiles[i].h = bytestream2_get_le16(gbc);
236
237 if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) {
238 av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n");
239 ret = AVERROR_INVALIDDATA;
240 goto end;
241 }
242
243 pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
244
245 ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
246 ctx->tiles[i].x, ctx->tiles[i].y,
247 ctx->tiles[i].w, ctx->tiles[i].h);
248
249 if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
250 av_log(avctx, AV_LOG_ERROR,
251 "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
252 ctx->tiles[i].x, ctx->tiles[i].y,
253 ctx->tiles[i].w, ctx->tiles[i].h);
254 ret = AVERROR_INVALIDDATA;
255 goto end;
256 } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
257 ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
258 av_log(avctx, AV_LOG_ERROR,
259 "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
260 ctx->tiles[i].x, ctx->tiles[i].y,
261 ctx->tiles[i].w, ctx->tiles[i].h);
262 ret = AVERROR_INVALIDDATA;
263 goto end;
264 }
265 }
266
267 /* Reset the reader in case it had been modified before */
268 gbc = &ctx->gbc;
269
270 /* Extract how much pixel data the tiles contain */
271 if (pixel_size < 0x100)
272 packed_size = bytestream2_get_byte(gbc);
273 else if (pixel_size < 0x10000)
274 packed_size = bytestream2_get_le16(gbc);
275 else if (pixel_size < 0x1000000)
276 packed_size = bytestream2_get_le24(gbc);
277 else
278 packed_size = bytestream2_get_le32(gbc);
279
280 ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
281
282 if (packed_size < 0) {
283 av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
284 ret = AVERROR_INVALIDDATA;
285 goto end;
286 }
287
288 /* Get pixels buffer, it may be deflated or just raw */
289 if (pixel_size == packed_size) {
290 if (bytestream2_get_bytes_left(gbc) < pixel_size) {
291 av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
292 ret = AVERROR_INVALIDDATA;
293 goto end;
294 }
295 pixels = gbc->buffer;
296 } else {
297 uLongf len = ctx->inflated_size;
298 if (bytestream2_get_bytes_left(gbc) < packed_size) {
299 av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
300 ret = AVERROR_INVALIDDATA;
301 goto end;
302 }
303 if (ctx->inflated_size < pixel_size) {
304 ret = AVERROR_INVALIDDATA;
305 goto end;
306 }
307 ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
308 if (ret) {
309 av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
310 ret = AVERROR_UNKNOWN;
311 goto end;
312 }
313 pixels = ctx->inflated_buf;
314 }
315
316 /* Allocate when needed */
317 ret = ff_reget_buffer(avctx, ctx->reference, 0);
318 if (ret < 0)
319 goto end;
320
321 /* Pointer to actual pixels, will be updated when data is consumed */
322 raw = pixels;
323 for (i = 0; i < tiles_nb; i++) {
324 uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
325 (avctx->height - ctx->tiles[i].y - 1) +
326 ctx->tiles[i].x * ctx->component_size;
327 av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
328 raw, ctx->tiles[i].w * ctx->component_size,
329 ctx->tiles[i].w * ctx->component_size,
330 ctx->tiles[i].h);
331 raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
332 }
333
334 /* Frame is ready to be output */
335 ret = av_frame_ref(frame, ctx->reference);
336 if (ret < 0)
337 goto end;
338
339 /* Keyframe when the number of pixels updated matches the whole surface */
340 if (pixel_size == ctx->inflated_size) {
341 frame->pict_type = AV_PICTURE_TYPE_I;
342 frame->key_frame = 1;
343 } else {
344 frame->pict_type = AV_PICTURE_TYPE_P;
345 }
346
347 /* Palette handling */
348 if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
349 buffer_size_t size;
350 const uint8_t *palette = av_packet_get_side_data(avpkt,
351 AV_PKT_DATA_PALETTE,
352 &size);
353 if (palette && size == AVPALETTE_SIZE) {
354 frame->palette_has_changed = 1;
355 memcpy(ctx->palette, palette, AVPALETTE_SIZE);
356 } else if (palette) {
357 av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
358 }
359 memcpy (frame->data[1], ctx->palette, AVPALETTE_SIZE);
360 }
361 // We only return a picture when enough of it is undamaged, this avoids copying nearly broken frames around
362 if (ctx->valid_pixels < ctx->inflated_size)
363 ctx->valid_pixels += pixel_size;
364 if (ctx->valid_pixels >= ctx->inflated_size * (100 - avctx->discard_damaged_percentage) / 100)
365 *got_frame = 1;
366
367 ret = avpkt->size;
368 end:
369 av_free(inflated_tiles);
370 return ret;
371 }
372
373 AVCodec ff_rscc_decoder = {
374 .name = "rscc",
375 .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
376 .type = AVMEDIA_TYPE_VIDEO,
377 .id = AV_CODEC_ID_RSCC,
378 .init = rscc_init,
379 .decode = rscc_decode_frame,
380 .close = rscc_close,
381 .priv_data_size = sizeof(RsccContext),
382 .capabilities = AV_CODEC_CAP_DR1,
383 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
384 FF_CODEC_CAP_INIT_CLEANUP,
385 };
386