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: BGRA, BGR24, RGB555, RGB8
41 #include "libavutil/imgutils.h"
42 #include "libavutil/internal.h"
45 #include "bytestream.h"
55 typedef struct RsccContext {
59 unsigned int tiles_size;
62 /* zlib interaction */
63 uint8_t *inflated_buf;
67 static av_cold int rscc_init(AVCodecContext *avctx)
69 RsccContext *ctx = avctx->priv_data;
71 /* These needs to be set to estimate uncompressed buffer */
72 int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
74 av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
75 avctx->width, avctx->height);
79 /* Allocate reference frame */
80 ctx->reference = av_frame_alloc();
82 return AVERROR(ENOMEM);
84 /* Get pixel format and the size of the pixel */
85 if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
86 avctx->pix_fmt = AV_PIX_FMT_BGRA;
87 ctx->component_size = 4;
88 } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
89 ctx->component_size = avctx->bits_per_coded_sample / 8;
90 switch (avctx->bits_per_coded_sample) {
92 avpriv_report_missing_feature(avctx, "8 bits per pixel");
93 return AVERROR_PATCHWELCOME;
95 avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
98 avctx->pix_fmt = AV_PIX_FMT_BGR24;
101 avctx->pix_fmt = AV_PIX_FMT_BGRA;
104 av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
105 avctx->bits_per_coded_sample);
106 return AVERROR_INVALIDDATA;
109 avctx->pix_fmt = AV_PIX_FMT_BGR0;
110 ctx->component_size = 4;
111 av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
114 /* Store the value to check for keyframes */
115 ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
117 /* Allocate maximum size possible, a full frame */
118 ctx->inflated_buf = av_malloc(ctx->inflated_size);
119 if (!ctx->inflated_buf)
120 return AVERROR(ENOMEM);
125 static av_cold int rscc_close(AVCodecContext *avctx)
127 RsccContext *ctx = avctx->priv_data;
129 av_freep(&ctx->tiles);
130 av_freep(&ctx->inflated_buf);
131 av_frame_free(&ctx->reference);
136 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
137 int *got_frame, AVPacket *avpkt)
139 RsccContext *ctx = avctx->priv_data;
140 GetByteContext *gbc = &ctx->gbc;
141 GetByteContext tiles_gbc;
142 AVFrame *frame = data;
143 const uint8_t *pixels, *raw;
144 uint8_t *inflated_tiles = NULL;
145 int tiles_nb, packed_size, pixel_size = 0;
148 bytestream2_init(gbc, avpkt->data, avpkt->size);
151 if (bytestream2_get_bytes_left(gbc) < 12) {
152 av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
153 return AVERROR_INVALIDDATA;
156 /* Read number of tiles, and allocate the array */
157 tiles_nb = bytestream2_get_le16(gbc);
158 av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
159 tiles_nb * sizeof(*ctx->tiles));
161 ret = AVERROR(ENOMEM);
165 av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
167 /* When there are more than 5 tiles, they are packed together with
168 * a size header. When that size does not match the number of tiles
169 * times the tile size, it means it needs to be inflated as well */
171 uLongf packed_tiles_size;
174 packed_tiles_size = bytestream2_get_byte(gbc);
176 packed_tiles_size = bytestream2_get_le16(gbc);
178 ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
180 /* If necessary, uncompress tiles, and hijack the bytestream reader */
181 if (packed_tiles_size != tiles_nb * TILE_SIZE) {
182 uLongf length = tiles_nb * TILE_SIZE;
183 inflated_tiles = av_malloc(length);
184 if (!inflated_tiles) {
185 ret = AVERROR(ENOMEM);
189 ret = uncompress(inflated_tiles, &length,
190 gbc->buffer, packed_tiles_size);
192 av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
193 ret = AVERROR_UNKNOWN;
197 /* Skip the compressed tile section in the main byte reader,
198 * and point it to read the newly uncompressed data */
199 bytestream2_skip(gbc, packed_tiles_size);
200 bytestream2_init(&tiles_gbc, inflated_tiles, length);
205 /* Fill in array of tiles, keeping track of how many pixels are updated */
206 for (i = 0; i < tiles_nb; i++) {
207 ctx->tiles[i].x = bytestream2_get_le16(gbc);
208 ctx->tiles[i].w = bytestream2_get_le16(gbc);
209 ctx->tiles[i].y = bytestream2_get_le16(gbc);
210 ctx->tiles[i].h = bytestream2_get_le16(gbc);
212 pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
214 ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
215 ctx->tiles[i].x, ctx->tiles[i].y,
216 ctx->tiles[i].w, ctx->tiles[i].h);
218 if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
219 av_log(avctx, AV_LOG_ERROR,
220 "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
221 ctx->tiles[i].x, ctx->tiles[i].y,
222 ctx->tiles[i].w, ctx->tiles[i].h);
223 ret = AVERROR_INVALIDDATA;
225 } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
226 ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
227 av_log(avctx, AV_LOG_ERROR,
228 "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
229 ctx->tiles[i].x, ctx->tiles[i].y,
230 ctx->tiles[i].w, ctx->tiles[i].h);
231 ret = AVERROR_INVALIDDATA;
236 /* Reset the reader in case it had been modified before */
239 /* Extract how much pixel data the tiles contain */
240 if (pixel_size < 0x100)
241 packed_size = bytestream2_get_byte(gbc);
242 else if (pixel_size < 0x10000)
243 packed_size = bytestream2_get_le16(gbc);
244 else if (pixel_size < 0x1000000)
245 packed_size = bytestream2_get_le24(gbc);
247 packed_size = bytestream2_get_le32(gbc);
249 ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
251 if (packed_size < 0) {
252 av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
253 ret = AVERROR_INVALIDDATA;
257 /* Get pixels buffer, it may be deflated or just raw */
258 if (pixel_size == packed_size) {
259 if (bytestream2_get_bytes_left(gbc) < pixel_size) {
260 av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
261 ret = AVERROR_INVALIDDATA;
264 pixels = gbc->buffer;
266 uLongf len = ctx->inflated_size;
267 if (bytestream2_get_bytes_left(gbc) < packed_size) {
268 av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
269 ret = AVERROR_INVALIDDATA;
272 ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
274 av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
275 ret = AVERROR_UNKNOWN;
278 pixels = ctx->inflated_buf;
281 /* Allocate when needed */
282 ret = ff_reget_buffer(avctx, ctx->reference);
286 /* Pointer to actual pixels, will be updated when data is consumed */
288 for (i = 0; i < tiles_nb; i++) {
289 uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
290 (avctx->height - ctx->tiles[i].y - 1) +
291 ctx->tiles[i].x * ctx->component_size;
292 av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
293 raw, ctx->tiles[i].w * ctx->component_size,
294 ctx->tiles[i].w * ctx->component_size,
296 raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
299 /* Frame is ready to be output */
300 ret = av_frame_ref(frame, ctx->reference);
304 /* Keyframe when the number of pixels updated matches the whole surface */
305 if (pixel_size == ctx->inflated_size) {
306 frame->pict_type = AV_PICTURE_TYPE_I;
307 frame->key_frame = 1;
309 frame->pict_type = AV_PICTURE_TYPE_P;
314 av_free(inflated_tiles);
318 AVCodec ff_rscc_decoder = {
320 .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
321 .type = AVMEDIA_TYPE_VIDEO,
322 .id = AV_CODEC_ID_RSCC,
324 .decode = rscc_decode_frame,
326 .priv_data_size = sizeof(RsccContext),
327 .capabilities = AV_CODEC_CAP_DR1,
328 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
329 FF_CODEC_CAP_INIT_CLEANUP,