2 * innoHeim/Rsupport Screen Capture Codec
3 * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
5 * This file is part of FFmpeg.
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.
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.
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
24 * innoHeim/Rsupport Screen Capture Codec decoder
28 * Lossless codec, data stored in tiles, with optional deflate compression.
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.
34 * Supports: PAL8, BGRA, BGR24, RGB555
41 #include "libavutil/imgutils.h"
42 #include "libavutil/internal.h"
45 #include "bytestream.h"
55 typedef struct RsccContext {
59 unsigned int tiles_size;
62 uint8_t palette[AVPALETTE_SIZE];
64 /* zlib interaction */
65 uint8_t *inflated_buf;
70 static av_cold int rscc_init(AVCodecContext *avctx)
72 RsccContext *ctx = avctx->priv_data;
74 /* These needs to be set to estimate uncompressed buffer */
75 int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
77 av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
78 avctx->width, avctx->height);
82 /* Allocate reference frame */
83 ctx->reference = av_frame_alloc();
85 return AVERROR(ENOMEM);
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;
94 avctx->pix_fmt = AV_PIX_FMT_BGR24;
95 ctx->component_size = 3;
98 avctx->pix_fmt = AV_PIX_FMT_BGRA;
99 ctx->component_size = 4;
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) {
105 avctx->pix_fmt = AV_PIX_FMT_PAL8;
108 avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
111 avctx->pix_fmt = AV_PIX_FMT_BGR24;
114 avctx->pix_fmt = AV_PIX_FMT_BGR0;
117 av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
118 avctx->bits_per_coded_sample);
119 return AVERROR_INVALIDDATA;
122 avctx->pix_fmt = AV_PIX_FMT_BGR0;
123 ctx->component_size = 4;
124 av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
127 /* Store the value to check for keyframes */
128 ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
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);
138 static av_cold int rscc_close(AVCodecContext *avctx)
140 RsccContext *ctx = avctx->priv_data;
142 av_freep(&ctx->tiles);
143 av_freep(&ctx->inflated_buf);
144 av_frame_free(&ctx->reference);
149 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
150 int *got_frame, AVPacket *avpkt)
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;
161 bytestream2_init(gbc, avpkt->data, avpkt->size);
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;
169 /* Read number of tiles, and allocate the array */
170 tiles_nb = bytestream2_get_le16(gbc);
173 av_log(avctx, AV_LOG_DEBUG, "no tiles\n");
177 av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
178 tiles_nb * sizeof(*ctx->tiles));
180 ret = AVERROR(ENOMEM);
184 av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
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 */
190 uLongf packed_tiles_size;
193 packed_tiles_size = bytestream2_get_byte(gbc);
195 packed_tiles_size = bytestream2_get_le16(gbc);
197 ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
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 inflated_tiles = av_malloc(length);
203 if (!inflated_tiles) {
204 ret = AVERROR(ENOMEM);
208 ret = uncompress(inflated_tiles, &length,
209 gbc->buffer, packed_tiles_size);
211 av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
212 ret = AVERROR_UNKNOWN;
216 /* Skip the compressed tile section in the main byte reader,
217 * and point it to read the newly uncompressed data */
218 bytestream2_skip(gbc, packed_tiles_size);
219 bytestream2_init(&tiles_gbc, inflated_tiles, length);
224 /* Fill in array of tiles, keeping track of how many pixels are updated */
225 for (i = 0; i < tiles_nb; i++) {
226 ctx->tiles[i].x = bytestream2_get_le16(gbc);
227 ctx->tiles[i].w = bytestream2_get_le16(gbc);
228 ctx->tiles[i].y = bytestream2_get_le16(gbc);
229 ctx->tiles[i].h = bytestream2_get_le16(gbc);
231 if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) {
232 av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n");
233 ret = AVERROR_INVALIDDATA;
237 pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
239 ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
240 ctx->tiles[i].x, ctx->tiles[i].y,
241 ctx->tiles[i].w, ctx->tiles[i].h);
243 if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
244 av_log(avctx, AV_LOG_ERROR,
245 "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
246 ctx->tiles[i].x, ctx->tiles[i].y,
247 ctx->tiles[i].w, ctx->tiles[i].h);
248 ret = AVERROR_INVALIDDATA;
250 } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
251 ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
252 av_log(avctx, AV_LOG_ERROR,
253 "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
254 ctx->tiles[i].x, ctx->tiles[i].y,
255 ctx->tiles[i].w, ctx->tiles[i].h);
256 ret = AVERROR_INVALIDDATA;
261 /* Reset the reader in case it had been modified before */
264 /* Extract how much pixel data the tiles contain */
265 if (pixel_size < 0x100)
266 packed_size = bytestream2_get_byte(gbc);
267 else if (pixel_size < 0x10000)
268 packed_size = bytestream2_get_le16(gbc);
269 else if (pixel_size < 0x1000000)
270 packed_size = bytestream2_get_le24(gbc);
272 packed_size = bytestream2_get_le32(gbc);
274 ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
276 if (packed_size < 0) {
277 av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
278 ret = AVERROR_INVALIDDATA;
282 /* Get pixels buffer, it may be deflated or just raw */
283 if (pixel_size == packed_size) {
284 if (bytestream2_get_bytes_left(gbc) < pixel_size) {
285 av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
286 ret = AVERROR_INVALIDDATA;
289 pixels = gbc->buffer;
291 uLongf len = ctx->inflated_size;
292 if (bytestream2_get_bytes_left(gbc) < packed_size) {
293 av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
294 ret = AVERROR_INVALIDDATA;
297 ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
299 av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
300 ret = AVERROR_UNKNOWN;
303 pixels = ctx->inflated_buf;
306 /* Allocate when needed */
307 ret = ff_reget_buffer(avctx, ctx->reference);
311 /* Pointer to actual pixels, will be updated when data is consumed */
313 for (i = 0; i < tiles_nb; i++) {
314 uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
315 (avctx->height - ctx->tiles[i].y - 1) +
316 ctx->tiles[i].x * ctx->component_size;
317 av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
318 raw, ctx->tiles[i].w * ctx->component_size,
319 ctx->tiles[i].w * ctx->component_size,
321 raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
324 /* Frame is ready to be output */
325 ret = av_frame_ref(frame, ctx->reference);
329 /* Keyframe when the number of pixels updated matches the whole surface */
330 if (pixel_size == ctx->inflated_size) {
331 frame->pict_type = AV_PICTURE_TYPE_I;
332 frame->key_frame = 1;
334 frame->pict_type = AV_PICTURE_TYPE_P;
337 /* Palette handling */
338 if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
340 const uint8_t *palette = av_packet_get_side_data(avpkt,
343 if (palette && size == AVPALETTE_SIZE) {
344 frame->palette_has_changed = 1;
345 memcpy(ctx->palette, palette, AVPALETTE_SIZE);
346 } else if (palette) {
347 av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
349 memcpy (frame->data[1], ctx->palette, AVPALETTE_SIZE);
351 // We only return a picture when enough of it is undamaged, this avoids copying nearly broken frames around
352 if (ctx->valid_pixels < ctx->inflated_size)
353 ctx->valid_pixels += pixel_size;
354 if (ctx->valid_pixels >= ctx->inflated_size * (100 - avctx->discard_damaged_percentage) / 100)
359 av_free(inflated_tiles);
363 AVCodec ff_rscc_decoder = {
365 .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
366 .type = AVMEDIA_TYPE_VIDEO,
367 .id = AV_CODEC_ID_RSCC,
369 .decode = rscc_decode_frame,
371 .priv_data_size = sizeof(RsccContext),
372 .capabilities = AV_CODEC_CAP_DR1,
373 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
374 FF_CODEC_CAP_INIT_CLEANUP,