FFmpeg
wcmv.c
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1 /*
2  * WinCAM Motion Video decoder
3  *
4  * Copyright (c) 2018 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 "libavutil/imgutils.h"
28 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "internal.h"
32 
33 #include <zlib.h>
34 
35 typedef struct WCMVContext {
36  int bpp;
37  z_stream zstream;
39  uint8_t block_data[65536*8];
40 } WCMVContext;
41 
42 static int decode_frame(AVCodecContext *avctx,
43  void *data, int *got_frame,
44  AVPacket *avpkt)
45 {
46  WCMVContext *s = avctx->priv_data;
47  AVFrame *frame = data;
48  int skip, blocks, zret, ret, intra = 0, flags = 0, bpp = s->bpp;
49  GetByteContext gb;
50  uint8_t *dst;
51 
52  ret = inflateReset(&s->zstream);
53  if (ret != Z_OK) {
54  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
55  return AVERROR_EXTERNAL;
56  }
57 
58  bytestream2_init(&gb, avpkt->data, avpkt->size);
59  blocks = bytestream2_get_le16(&gb);
60  if (!blocks)
62 
63  if ((ret = ff_reget_buffer(avctx, s->prev_frame, flags)) < 0)
64  return ret;
65 
66  if (blocks > 5) {
67  GetByteContext bgb;
68  int x = 0, size;
69 
70  if (blocks * 8 >= 0xFFFF)
71  size = bytestream2_get_le24(&gb);
72  else if (blocks * 8 >= 0xFF)
73  size = bytestream2_get_le16(&gb);
74  else
75  size = bytestream2_get_byte(&gb);
76 
77  skip = bytestream2_tell(&gb);
78  if (size > avpkt->size - skip)
79  return AVERROR_INVALIDDATA;
80 
81  s->zstream.next_in = avpkt->data + skip;
82  s->zstream.avail_in = size;
83  s->zstream.next_out = s->block_data;
84  s->zstream.avail_out = sizeof(s->block_data);
85 
86  zret = inflate(&s->zstream, Z_FINISH);
87  if (zret != Z_STREAM_END) {
88  av_log(avctx, AV_LOG_ERROR,
89  "Inflate failed with return code: %d.\n", zret);
90  return AVERROR_INVALIDDATA;
91  }
92 
93  ret = inflateReset(&s->zstream);
94  if (ret != Z_OK) {
95  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
96  return AVERROR_EXTERNAL;
97  }
98 
99  bytestream2_skip(&gb, size);
100  bytestream2_init(&bgb, s->block_data, blocks * 8);
101 
102  for (int i = 0; i < blocks; i++) {
103  int w, h;
104 
105  bytestream2_skip(&bgb, 4);
106  w = bytestream2_get_le16(&bgb);
107  h = bytestream2_get_le16(&bgb);
108  if (x + bpp * (int64_t)w * h > INT_MAX)
109  return AVERROR_INVALIDDATA;
110  x += bpp * w * h;
111  }
112 
113  if (x >= 0xFFFF)
114  bytestream2_skip(&gb, 3);
115  else if (x >= 0xFF)
116  bytestream2_skip(&gb, 2);
117  else
118  bytestream2_skip(&gb, 1);
119 
120  skip = bytestream2_tell(&gb);
121 
122  s->zstream.next_in = avpkt->data + skip;
123  s->zstream.avail_in = avpkt->size - skip;
124 
125  bytestream2_init(&gb, s->block_data, blocks * 8);
126  } else if (blocks) {
127  int x = 0;
128 
129  bytestream2_seek(&gb, 2, SEEK_SET);
130 
131  for (int i = 0; i < blocks; i++) {
132  int w, h;
133 
134  bytestream2_skip(&gb, 4);
135  w = bytestream2_get_le16(&gb);
136  h = bytestream2_get_le16(&gb);
137  if (x + bpp * (int64_t)w * h > INT_MAX)
138  return AVERROR_INVALIDDATA;
139  x += bpp * w * h;
140  }
141 
142  if (x >= 0xFFFF)
143  bytestream2_skip(&gb, 3);
144  else if (x >= 0xFF)
145  bytestream2_skip(&gb, 2);
146  else
147  bytestream2_skip(&gb, 1);
148 
149  skip = bytestream2_tell(&gb);
150 
151  s->zstream.next_in = avpkt->data + skip;
152  s->zstream.avail_in = avpkt->size - skip;
153 
154  bytestream2_seek(&gb, 2, SEEK_SET);
155  }
156 
157  if (bytestream2_get_bytes_left(&gb) < 8LL * blocks)
158  return AVERROR_INVALIDDATA;
159 
160  if (!avctx->frame_number) {
161  ptrdiff_t linesize[4] = { s->prev_frame->linesize[0], 0, 0, 0 };
162  av_image_fill_black(s->prev_frame->data, linesize, avctx->pix_fmt, 0,
163  avctx->width, avctx->height);
164  }
165 
166  for (int block = 0; block < blocks; block++) {
167  int x, y, w, h;
168 
169  x = bytestream2_get_le16(&gb);
170  y = bytestream2_get_le16(&gb);
171  w = bytestream2_get_le16(&gb);
172  h = bytestream2_get_le16(&gb);
173 
174  if (blocks == 1 && x == 0 && y == 0 && w == avctx->width && h == avctx->height)
175  intra = 1;
176 
177  if (x + w > avctx->width || y + h > avctx->height)
178  return AVERROR_INVALIDDATA;
179 
180  if (w > avctx->width || h > avctx->height)
181  return AVERROR_INVALIDDATA;
182 
183  dst = s->prev_frame->data[0] + (avctx->height - y - 1) * s->prev_frame->linesize[0] + x * bpp;
184  for (int i = 0; i < h; i++) {
185  s->zstream.next_out = dst;
186  s->zstream.avail_out = w * bpp;
187 
188  zret = inflate(&s->zstream, Z_SYNC_FLUSH);
189  if (zret != Z_OK && zret != Z_STREAM_END) {
190  av_log(avctx, AV_LOG_ERROR,
191  "Inflate failed with return code: %d.\n", zret);
192  return AVERROR_INVALIDDATA;
193  }
194 
195  dst -= s->prev_frame->linesize[0];
196  }
197  }
198 
199  s->prev_frame->key_frame = intra;
201 
202  if ((ret = av_frame_ref(frame, s->prev_frame)) < 0)
203  return ret;
204 
205  *got_frame = 1;
206 
207  return avpkt->size;
208 }
209 
211 {
212  WCMVContext *s = avctx->priv_data;
213  int zret;
214 
215  switch (avctx->bits_per_coded_sample) {
216  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB565LE; break;
217  case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
218  case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
219  default: av_log(avctx, AV_LOG_ERROR, "Unsupported bits_per_coded_sample: %d\n",
220  avctx->bits_per_coded_sample);
221  return AVERROR_PATCHWELCOME;
222  }
223 
224  s->bpp = avctx->bits_per_coded_sample >> 3;
225 
226  s->zstream.zalloc = Z_NULL;
227  s->zstream.zfree = Z_NULL;
228  s->zstream.opaque = Z_NULL;
229  zret = inflateInit(&s->zstream);
230  if (zret != Z_OK) {
231  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
232  return AVERROR_EXTERNAL;
233  }
234 
235  s->prev_frame = av_frame_alloc();
236  if (!s->prev_frame)
237  return AVERROR(ENOMEM);
238 
239  return 0;
240 }
241 
243 {
244  WCMVContext *s = avctx->priv_data;
245 
247  inflateEnd(&s->zstream);
248 
249  return 0;
250 }
251 
253  .name = "wcmv",
254  .long_name = NULL_IF_CONFIG_SMALL("WinCAM Motion Video"),
255  .type = AVMEDIA_TYPE_VIDEO,
256  .id = AV_CODEC_ID_WCMV,
257  .priv_data_size = sizeof(WCMVContext),
258  .init = decode_init,
259  .close = decode_close,
260  .decode = decode_frame,
261  .capabilities = AV_CODEC_CAP_DR1,
262  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
264 };
#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
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
misc image utilities
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1481
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
AVCodec.
Definition: avcodec.h:3492
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), little-endian
Definition: pixfmt.h:106
AVCodec ff_wcmv_decoder
Definition: wcmv.c:252
static av_cold int decode_close(AVCodecContext *avctx)
Definition: wcmv.c:242
#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:40
The exact code depends on how similar the blocks are and how related they are to the block
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:443
uint8_t * data
Definition: avcodec.h:1480
#define FF_REGET_BUFFER_FLAG_READONLY
the returned buffer does not need to be writable
Definition: internal.h:323
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
#define av_log(a,...)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available...
Definition: decode.c:2015
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
uint8_t block_data[65536 *8]
Definition: wcmv.c:39
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
int bpp
Definition: wcmv.c:36
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
int width
picture width / height.
Definition: avcodec.h:1741
uint8_t w
Definition: llviddspenc.c:38
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
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
static av_cold int decode_init(AVCodecContext *avctx)
Definition: wcmv.c:210
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:188
Libavcodec external API header.
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
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
AVFrame * prev_frame
Definition: wcmv.c:38
#define flags(name, subs,...)
Definition: cbs_av1.c:561
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
common internal api header.
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: wcmv.c:42
void * priv_data
Definition: avcodec.h:1595
int av_image_fill_black(uint8_t *dst_data[4], const ptrdiff_t dst_linesize[4], enum AVPixelFormat pix_fmt, enum AVColorRange range, int width, int height)
Overwrite the image data with black.
Definition: imgutils.c:534
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:208
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2259
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
z_stream zstream
Definition: wcmv.c:37
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:57
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
for(j=16;j >0;--j)
Predicted.
Definition: avutil.h:275