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;
37  unsigned int uncomp_size;
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  int 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, "Palette size %d is wrong\n", size);
164  }
165  memcpy(frame->data[1], s->pal, AVPALETTE_SIZE);
166  }
167 
168  ret = inflateReset(&s->zstream);
169  if (ret != Z_OK) {
170  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
171  return AVERROR_UNKNOWN;
172  }
173  s->zstream.next_in = buf;
174  s->zstream.avail_in = buf_size;
175  s->zstream.next_out = s->decomp_buf;
176  s->zstream.avail_out = s->decomp_size;
177  ret = inflate(&s->zstream, Z_FINISH);
178  if (ret != Z_STREAM_END) {
179  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
180  return AVERROR_UNKNOWN;
181  }
182 
183  bytestream2_init(&gb, s->decomp_buf, s->zstream.total_out);
185 
186  ret = rle_uncompress(avctx, &gb, &pb);
187  if (ret)
188  return ret;
189 
190  for (j = 0; j < avctx->height; j++) {
191  memcpy(frame->data[0] + (avctx->height - j - 1) * frame->linesize[0],
192  s->uncomp_buf + s->bpp * j * avctx->width, s->bpp * avctx->width);
193  }
194 
195  frame->key_frame = 1;
196  frame->pict_type = AV_PICTURE_TYPE_I;
197 
198  *got_frame = 1;
199 
200  return avpkt->size;
201 }
202 
204 {
205  MSCCContext *s = avctx->priv_data;
206  int stride, zret;
207 
208  switch (avctx->bits_per_coded_sample) {
209  case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
210  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
211  case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
212  case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
213  default:
214  av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
215  return AVERROR_INVALIDDATA;
216  }
217 
218  s->bpp = avctx->bits_per_coded_sample >> 3;
219  stride = 4 * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
220 
221  s->decomp_size = 2 * avctx->height * stride;
222  if (!(s->decomp_buf = av_malloc(s->decomp_size)))
223  return AVERROR(ENOMEM);
224 
225  s->uncomp_size = avctx->height * stride;
226  if (!(s->uncomp_buf = av_malloc(s->uncomp_size)))
227  return AVERROR(ENOMEM);
228 
229  s->zstream.zalloc = Z_NULL;
230  s->zstream.zfree = Z_NULL;
231  s->zstream.opaque = Z_NULL;
232  zret = inflateInit(&s->zstream);
233  if (zret != Z_OK) {
234  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
235  return AVERROR_UNKNOWN;
236  }
237 
238  return 0;
239 }
240 
242 {
243  MSCCContext *s = avctx->priv_data;
244 
245  av_freep(&s->decomp_buf);
246  s->decomp_size = 0;
247  av_freep(&s->uncomp_buf);
248  s->uncomp_size = 0;
249  inflateEnd(&s->zstream);
250 
251  return 0;
252 }
253 
255  .name = "mscc",
256  .long_name = NULL_IF_CONFIG_SMALL("Mandsoft Screen Capture Codec"),
257  .type = AVMEDIA_TYPE_VIDEO,
258  .id = AV_CODEC_ID_MSCC,
259  .priv_data_size = sizeof(MSCCContext),
260  .init = decode_init,
261  .close = decode_close,
262  .decode = decode_frame,
263  .capabilities = AV_CODEC_CAP_DR1,
264  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
265 };
266 
268  .name = "srgc",
269  .long_name = NULL_IF_CONFIG_SMALL("Screen Recorder Gold Codec"),
270  .type = AVMEDIA_TYPE_VIDEO,
271  .id = AV_CODEC_ID_SRGC,
272  .priv_data_size = sizeof(MSCCContext),
273  .init = decode_init,
274  .close = decode_close,
275  .decode = decode_frame,
276  .capabilities = AV_CODEC_CAP_DR1,
277  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
278 };
#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:48
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static void copy(const float *p1, float *p2, const int length)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1481
static av_always_inline void bytestream2_init_writer(PutByteContext *p, uint8_t *buf, int buf_size)
Definition: bytestream.h:143
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
uint8_t run
Definition: svq3.c:206
AVCodec.
Definition: avcodec.h:3492
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
static int rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb)
Definition: mscc.c:44
uint8_t * data
Definition: avcodec.h:1480
ptrdiff_t size
Definition: opengl_enc.c:100
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2792
unsigned bpp
Definition: mscc.c:34
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1193
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
static av_cold int decode_init(AVCodecContext *avctx)
Definition: mscc.c:203
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
AVCodec ff_mscc_decoder
Definition: mscc.c:254
unsigned int decomp_size
Definition: mscc.c:35
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
z_stream zstream
Definition: mscc.c:39
int width
picture width / height.
Definition: avcodec.h:1741
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
#define s(width, name)
Definition: cbs_vp9.c:257
unsigned int uncomp_size
Definition: mscc.c:37
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
static av_always_inline int bytestream2_seek_p(PutByteContext *p, int offset, int whence)
Definition: bytestream.h:232
AVCodec ff_srgc_decoder
Definition: mscc.c:267
Libavcodec external API header.
enum AVCodecID codec_id
Definition: avcodec.h:1578
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
main external API structure.
Definition: avcodec.h:1568
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1968
void * buf
Definition: avisynth_c.h:766
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:197
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:452
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
common internal api header.
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:375
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mscc.c:130
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1595
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
uint32_t pal[256]
Definition: mscc.c:41
#define av_freep(p)
#define stride
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:984
uint8_t * decomp_buf
Definition: mscc.c:36
uint8_t * uncomp_buf
Definition: mscc.c:38
static av_cold int decode_close(AVCodecContext *avctx)
Definition: mscc.c:241