FFmpeg
mscc.c
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1 /*
2  * Mandsoft Screen Capture Codec decoder
3  *
4  * Copyright (c) 2017 Paul B Mahol
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "internal.h"
30 
31 #include <zlib.h>
32 
33 typedef struct MSCCContext {
34  unsigned bpp;
35  unsigned int decomp_size;
36  uint8_t *decomp_buf;
37  unsigned int uncomp_size;
38  uint8_t *uncomp_buf;
39  z_stream zstream;
40 
41  uint32_t pal[256];
42 } MSCCContext;
43 
45 {
46  MSCCContext *s = avctx->priv_data;
47  unsigned x = 0, y = 0;
48 
49  while (bytestream2_get_bytes_left(gb) > 0) {
50  uint32_t fill;
51  int j;
52  unsigned run = bytestream2_get_byte(gb);
53 
54  if (run) {
55  switch (avctx->bits_per_coded_sample) {
56  case 8:
57  fill = bytestream2_get_byte(gb);
58  break;
59  case 16:
60  fill = bytestream2_get_le16(gb);
61  break;
62  case 24:
63  fill = bytestream2_get_le24(gb);
64  break;
65  case 32:
66  fill = bytestream2_get_le32(gb);
67  break;
68  }
69 
70  for (j = 0; j < run; j++) {
71  switch (avctx->bits_per_coded_sample) {
72  case 8:
73  bytestream2_put_byte(pb, fill);
74  break;
75  case 16:
76  bytestream2_put_le16(pb, fill);
77  break;
78  case 24:
79  bytestream2_put_le24(pb, fill);
80  break;
81  case 32:
82  bytestream2_put_le32(pb, fill);
83  break;
84  }
85  }
86  x += run;
87  } else {
88  unsigned copy = bytestream2_get_byte(gb);
89 
90  if (copy == 0) {
91  x = 0;
92  y++;
93  bytestream2_seek_p(pb, y * avctx->width * s->bpp, SEEK_SET);
94  } else if (copy == 1) {
95  return 0;
96  } else if (copy == 2) {
97 
98  x += bytestream2_get_byte(gb);
99  y += bytestream2_get_byte(gb);
100 
101  bytestream2_seek_p(pb, y * avctx->width * s->bpp + x * s->bpp, SEEK_SET);
102  } else {
103  for (j = 0; j < copy; j++) {
104  switch (avctx->bits_per_coded_sample) {
105  case 8:
106  bytestream2_put_byte(pb, bytestream2_get_byte(gb));
107  break;
108  case 16:
109  bytestream2_put_le16(pb, bytestream2_get_le16(gb));
110  break;
111  case 24:
112  bytestream2_put_le24(pb, bytestream2_get_le24(gb));
113  break;
114  case 32:
115  bytestream2_put_le32(pb, bytestream2_get_le32(gb));
116  break;
117  }
118  }
119 
120  if (s->bpp == 1 && (copy & 1))
121  bytestream2_skip(gb, 1);
122  x += copy;
123  }
124  }
125  }
126 
127  return AVERROR_INVALIDDATA;
128 }
129 
130 static int decode_frame(AVCodecContext *avctx,
131  void *data, int *got_frame,
132  AVPacket *avpkt)
133 {
134  MSCCContext *s = avctx->priv_data;
135  AVFrame *frame = data;
136  uint8_t *buf = avpkt->data;
137  int buf_size = avpkt->size;
138  GetByteContext gb;
139  PutByteContext pb;
140  int ret, j;
141 
142  if (avpkt->size < 3)
143  return buf_size;
144 
145  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
146  return ret;
147 
148  if (avctx->codec_id == AV_CODEC_ID_MSCC) {
149  avpkt->data[2] ^= avpkt->data[0];
150  buf += 2;
151  buf_size -= 2;
152  }
153 
154  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
155  size_t size;
156  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
157 
158  if (pal && size == AVPALETTE_SIZE) {
159  frame->palette_has_changed = 1;
160  for (j = 0; j < 256; j++)
161  s->pal[j] = 0xFF000000 | AV_RL32(pal + j * 4);
162  } else if (pal) {
163  av_log(avctx, AV_LOG_ERROR,
164  "Palette size %"SIZE_SPECIFIER" is wrong\n", size);
165  }
166  memcpy(frame->data[1], s->pal, AVPALETTE_SIZE);
167  }
168 
169  ret = inflateReset(&s->zstream);
170  if (ret != Z_OK) {
171  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
172  return AVERROR_UNKNOWN;
173  }
174  s->zstream.next_in = buf;
175  s->zstream.avail_in = buf_size;
176  s->zstream.next_out = s->decomp_buf;
177  s->zstream.avail_out = s->decomp_size;
178  ret = inflate(&s->zstream, Z_FINISH);
179  if (ret != Z_STREAM_END) {
180  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
181  return AVERROR_UNKNOWN;
182  }
183 
184  bytestream2_init(&gb, s->decomp_buf, s->zstream.total_out);
185  bytestream2_init_writer(&pb, s->uncomp_buf, s->uncomp_size);
186 
187  ret = rle_uncompress(avctx, &gb, &pb);
188  if (ret)
189  return ret;
190 
191  for (j = 0; j < avctx->height; j++) {
192  memcpy(frame->data[0] + (avctx->height - j - 1) * frame->linesize[0],
193  s->uncomp_buf + s->bpp * j * avctx->width, s->bpp * avctx->width);
194  }
195 
196  frame->key_frame = 1;
197  frame->pict_type = AV_PICTURE_TYPE_I;
198 
199  *got_frame = 1;
200 
201  return avpkt->size;
202 }
203 
205 {
206  MSCCContext *s = avctx->priv_data;
207  int stride, zret;
208 
209  switch (avctx->bits_per_coded_sample) {
210  case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
211  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
212  case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
213  case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
214  default:
215  av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
216  return AVERROR_INVALIDDATA;
217  }
218 
219  s->bpp = avctx->bits_per_coded_sample >> 3;
220  stride = 4 * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
221 
222  s->decomp_size = 2 * avctx->height * stride;
223  if (!(s->decomp_buf = av_malloc(s->decomp_size)))
224  return AVERROR(ENOMEM);
225 
226  s->uncomp_size = avctx->height * stride;
227  if (!(s->uncomp_buf = av_malloc(s->uncomp_size)))
228  return AVERROR(ENOMEM);
229 
230  s->zstream.zalloc = Z_NULL;
231  s->zstream.zfree = Z_NULL;
232  s->zstream.opaque = Z_NULL;
233  zret = inflateInit(&s->zstream);
234  if (zret != Z_OK) {
235  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
236  return AVERROR_UNKNOWN;
237  }
238 
239  return 0;
240 }
241 
243 {
244  MSCCContext *s = avctx->priv_data;
245 
246  av_freep(&s->decomp_buf);
247  s->decomp_size = 0;
248  av_freep(&s->uncomp_buf);
249  s->uncomp_size = 0;
250  inflateEnd(&s->zstream);
251 
252  return 0;
253 }
254 
256  .name = "mscc",
257  .long_name = NULL_IF_CONFIG_SMALL("Mandsoft Screen Capture Codec"),
258  .type = AVMEDIA_TYPE_VIDEO,
259  .id = AV_CODEC_ID_MSCC,
260  .priv_data_size = sizeof(MSCCContext),
261  .init = decode_init,
262  .close = decode_close,
263  .decode = decode_frame,
264  .capabilities = AV_CODEC_CAP_DR1,
266 };
267 
269  .name = "srgc",
270  .long_name = NULL_IF_CONFIG_SMALL("Screen Recorder Gold Codec"),
271  .type = AVMEDIA_TYPE_VIDEO,
272  .id = AV_CODEC_ID_SRGC,
273  .priv_data_size = sizeof(MSCCContext),
274  .init = decode_init,
275  .close = decode_close,
276  .decode = decode_frame,
277  .capabilities = AV_CODEC_CAP_DR1,
279 };
AVCodec
AVCodec.
Definition: codec.h:197
stride
int stride
Definition: mace.c:144
AV_CODEC_ID_MSCC
@ AV_CODEC_ID_MSCC
Definition: codec_id.h:280
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:41
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
MSCCContext::uncomp_buf
uint8_t * uncomp_buf
Definition: mscc.c:38
GetByteContext
Definition: bytestream.h:33
AV_CODEC_ID_SRGC
@ AV_CODEC_ID_SRGC
Definition: codec_id.h:281
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mscc.c:130
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:365
AV_PKT_DATA_PALETTE
@ AV_PKT_DATA_PALETTE
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette.
Definition: packet.h:46
data
const char data[16]
Definition: mxf.c:142
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
AV_PIX_FMT_BGRA
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
inflate
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:198
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:181
av_cold
#define av_cold
Definition: attributes.h:90
bytestream2_init_writer
static av_always_inline void bytestream2_init_writer(PutByteContext *p, uint8_t *buf, int buf_size)
Definition: bytestream.h:147
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
s
#define s(width, name)
Definition: cbs_vp9.c:257
MSCCContext
Definition: mscc.c:33
ff_srgc_decoder
const AVCodec ff_srgc_decoder
Definition: mscc.c:268
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:511
run
uint8_t run
Definition: svq3.c:203
MSCCContext::bpp
unsigned bpp
Definition: mscc.c:34
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
MSCCContext::decomp_buf
uint8_t * decomp_buf
Definition: mscc.c:36
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
MSCCContext::pal
uint32_t pal[256]
Definition: mscc.c:41
PutByteContext
Definition: bytestream.h:37
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1638
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:366
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
copy
static void copy(const float *p1, float *p2, const int length)
Definition: vf_vaguedenoiser.c:194
rle_uncompress
static int rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb)
Definition: mscc.c:44
size
int size
Definition: twinvq_data.h:10344
MSCCContext::uncomp_size
unsigned int uncomp_size
Definition: mscc.c:37
ff_mscc_decoder
const AVCodec ff_mscc_decoder
Definition: mscc.c:255
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1524
MSCCContext::decomp_size
unsigned int decomp_size
Definition: mscc.c:35
decode_close
static av_cold int decode_close(AVCodecContext *avctx)
Definition: mscc.c:242
av_packet_get_side_data
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, size_t *size)
Get side information from packet.
Definition: avpacket.c:241
FF_CODEC_CAP_INIT_CLEANUP
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:49
AV_PIX_FMT_RGB555
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:377
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:204
MSCCContext::zstream
z_stream zstream
Definition: mscc.c:39
AVCodecContext::height
int height
Definition: avcodec.h:674
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:711
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
SIZE_SPECIFIER
#define SIZE_SPECIFIER
Definition: internal.h:193
AVCodecContext
main external API structure.
Definition: avcodec.h:501
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: mscc.c:204
bytestream2_seek_p
static av_always_inline int bytestream2_seek_p(PutByteContext *p, int offset, int whence)
Definition: bytestream.h:236
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVPacket
This structure stores compressed data.
Definition: packet.h:342
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:528
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:674
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59