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 
25 #include "libavutil/imgutils.h"
26 
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "codec_internal.h"
30 #include "decode.h"
31 #include "zlib_wrapper.h"
32 
33 #include <zlib.h>
34 
35 typedef struct WCMVContext {
36  int bpp;
39  uint8_t block_data[65536*8];
40 } WCMVContext;
41 
43  int *got_frame, AVPacket *avpkt)
44 {
45  WCMVContext *s = avctx->priv_data;
46  z_stream *const zstream = &s->zstream.zstream;
47  int skip, blocks, zret, ret, intra = 0, flags = 0, bpp = s->bpp;
48  GetByteContext gb;
49  uint8_t *dst;
50 
51  ret = inflateReset(zstream);
52  if (ret != Z_OK) {
53  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
54  return AVERROR_EXTERNAL;
55  }
56 
57  bytestream2_init(&gb, avpkt->data, avpkt->size);
58  blocks = bytestream2_get_le16(&gb);
59  if (!blocks)
61 
62  if ((ret = ff_reget_buffer(avctx, s->prev_frame, flags)) < 0)
63  return ret;
64 
65  if (blocks > 5) {
66  GetByteContext bgb;
67  int x = 0, size;
68 
69  if (blocks * 8 >= 0xFFFF)
70  size = bytestream2_get_le24(&gb);
71  else if (blocks * 8 >= 0xFF)
72  size = bytestream2_get_le16(&gb);
73  else
74  size = bytestream2_get_byte(&gb);
75 
76  skip = bytestream2_tell(&gb);
77  if (size > avpkt->size - skip)
78  return AVERROR_INVALIDDATA;
79 
80  zstream->next_in = avpkt->data + skip;
81  zstream->avail_in = size;
82  zstream->next_out = s->block_data;
83  zstream->avail_out = sizeof(s->block_data);
84 
85  zret = inflate(zstream, Z_FINISH);
86  if (zret != Z_STREAM_END) {
87  av_log(avctx, AV_LOG_ERROR,
88  "Inflate failed with return code: %d.\n", zret);
89  return AVERROR_INVALIDDATA;
90  }
91 
92  ret = inflateReset(zstream);
93  if (ret != Z_OK) {
94  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
95  return AVERROR_EXTERNAL;
96  }
97 
98  bytestream2_skip(&gb, size);
99  bytestream2_init(&bgb, s->block_data, blocks * 8);
100 
101  for (int i = 0; i < blocks; i++) {
102  int w, h;
103 
104  bytestream2_skip(&bgb, 4);
105  w = bytestream2_get_le16(&bgb);
106  h = bytestream2_get_le16(&bgb);
107  if (x + bpp * (int64_t)w * h > INT_MAX)
108  return AVERROR_INVALIDDATA;
109  x += bpp * w * h;
110  }
111 
112  if (x >= 0xFFFF)
113  bytestream2_skip(&gb, 3);
114  else if (x >= 0xFF)
115  bytestream2_skip(&gb, 2);
116  else
117  bytestream2_skip(&gb, 1);
118 
119  skip = bytestream2_tell(&gb);
120 
121  zstream->next_in = avpkt->data + skip;
122  zstream->avail_in = avpkt->size - skip;
123 
124  bytestream2_init(&gb, s->block_data, blocks * 8);
125  } else if (blocks) {
126  int x = 0;
127 
128  bytestream2_seek(&gb, 2, SEEK_SET);
129 
130  for (int i = 0; i < blocks; i++) {
131  int w, h;
132 
133  bytestream2_skip(&gb, 4);
134  w = bytestream2_get_le16(&gb);
135  h = bytestream2_get_le16(&gb);
136  if (x + bpp * (int64_t)w * h > INT_MAX)
137  return AVERROR_INVALIDDATA;
138  x += bpp * w * h;
139  }
140 
141  if (x >= 0xFFFF)
142  bytestream2_skip(&gb, 3);
143  else if (x >= 0xFF)
144  bytestream2_skip(&gb, 2);
145  else
146  bytestream2_skip(&gb, 1);
147 
148  skip = bytestream2_tell(&gb);
149 
150  zstream->next_in = avpkt->data + skip;
151  zstream->avail_in = avpkt->size - skip;
152 
153  bytestream2_seek(&gb, 2, SEEK_SET);
154  }
155 
156  if (bytestream2_get_bytes_left(&gb) < 8LL * blocks)
157  return AVERROR_INVALIDDATA;
158 
159  if (!avctx->frame_num) {
160  ptrdiff_t linesize[4] = { s->prev_frame->linesize[0], 0, 0, 0 };
161  av_image_fill_black(s->prev_frame->data, linesize, avctx->pix_fmt, 0,
162  avctx->width, avctx->height);
163  }
164 
165  for (int block = 0; block < blocks; block++) {
166  int x, y, w, h;
167 
168  x = bytestream2_get_le16(&gb);
169  y = bytestream2_get_le16(&gb);
170  w = bytestream2_get_le16(&gb);
171  h = bytestream2_get_le16(&gb);
172 
173  if (blocks == 1 && x == 0 && y == 0 && w == avctx->width && h == avctx->height)
174  intra = 1;
175 
176  if (x + w > avctx->width || y + h > avctx->height)
177  return AVERROR_INVALIDDATA;
178 
179  if (w > avctx->width || h > avctx->height)
180  return AVERROR_INVALIDDATA;
181 
182  dst = s->prev_frame->data[0] + (avctx->height - y - 1) * s->prev_frame->linesize[0] + x * bpp;
183  for (int i = 0; i < h; i++) {
184  zstream->next_out = dst;
185  zstream->avail_out = w * bpp;
186 
187  zret = inflate(zstream, Z_SYNC_FLUSH);
188  if (zret != Z_OK && zret != Z_STREAM_END) {
189  av_log(avctx, AV_LOG_ERROR,
190  "Inflate failed with return code: %d.\n", zret);
191  return AVERROR_INVALIDDATA;
192  }
193 
194  dst -= s->prev_frame->linesize[0];
195  }
196  }
197 
198  if (intra)
199  s->prev_frame->flags |= AV_FRAME_FLAG_KEY;
200  else
201  s->prev_frame->flags &= ~AV_FRAME_FLAG_KEY;
202  s->prev_frame->pict_type = intra ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
203 
204  if ((ret = av_frame_ref(frame, s->prev_frame)) < 0)
205  return ret;
206 
207  *got_frame = 1;
208 
209  return avpkt->size;
210 }
211 
213 {
214  WCMVContext *s = avctx->priv_data;
215 
216  switch (avctx->bits_per_coded_sample) {
217  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB565LE; break;
218  case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
219  case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
220  default: av_log(avctx, AV_LOG_ERROR, "Unsupported bits_per_coded_sample: %d\n",
221  avctx->bits_per_coded_sample);
222  return AVERROR_PATCHWELCOME;
223  }
224 
225  s->bpp = avctx->bits_per_coded_sample >> 3;
226 
227  s->prev_frame = av_frame_alloc();
228  if (!s->prev_frame)
229  return AVERROR(ENOMEM);
230 
231  return ff_inflate_init(&s->zstream, avctx);
232 }
233 
235 {
236  WCMVContext *s = avctx->priv_data;
237 
238  av_frame_free(&s->prev_frame);
239  ff_inflate_end(&s->zstream);
240 
241  return 0;
242 }
243 
245  .p.name = "wcmv",
246  CODEC_LONG_NAME("WinCAM Motion Video"),
247  .p.type = AVMEDIA_TYPE_VIDEO,
248  .p.id = AV_CODEC_ID_WCMV,
249  .priv_data_size = sizeof(WCMVContext),
250  .init = decode_init,
251  .close = decode_close,
253  .p.capabilities = AV_CODEC_CAP_DR1,
254  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
255 };
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: codec_internal.h:42
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
GetByteContext
Definition: bytestream.h:33
WCMVContext
Definition: wcmv.c:35
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:100
bytestream2_seek
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:212
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
w
uint8_t w
Definition: llviddspenc.c:38
AVPacket::data
uint8_t * data
Definition: packet.h:491
FFCodec
Definition: codec_internal.h:127
WCMVContext::prev_frame
AVFrame * prev_frame
Definition: wcmv.c:38
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
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
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:194
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:88
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
zlib_wrapper.h
av_cold
#define av_cold
Definition: attributes.h:90
AV_FRAME_FLAG_KEY
#define AV_FRAME_FLAG_KEY
A flag to mark frames that are keyframes.
Definition: frame.h:628
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
s
#define s(width, name)
Definition: cbs_vp9.c:198
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts_bsf.c:365
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
WCMVContext::block_data
uint8_t block_data[65536 *8]
Definition: wcmv.c:39
frame
static AVFrame * frame
Definition: demux_decode.c:54
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)
Definition: wcmv.c:42
AV_PIX_FMT_RGB565LE
@ AV_PIX_FMT_RGB565LE
packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), little-endian
Definition: pixfmt.h:106
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
ff_wcmv_decoder
const FFCodec ff_wcmv_decoder
Definition: wcmv.c:244
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:279
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
bytestream2_tell
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:192
AV_CODEC_ID_WCMV
@ AV_CODEC_ID_WCMV
Definition: codec_id.h:293
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:492
WCMVContext::zstream
FFZStream zstream
Definition: wcmv.c:37
av_frame_ref
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:361
codec_internal.h
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
size
int size
Definition: twinvq_data.h:10344
av_image_fill_black
int av_image_fill_black(uint8_t *const 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:582
AVERROR_EXTERNAL
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:59
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1510
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:245
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
ff_inflate_end
void ff_inflate_end(FFZStream *zstream)
Wrapper around inflateEnd().
AVCodecContext::height
int height
Definition: avcodec.h:621
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:658
avcodec.h
AVCodecContext::frame_num
int64_t frame_num
Frame counter, set by libavcodec.
Definition: avcodec.h:2118
ff_reget_buffer
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:1735
ret
ret
Definition: filter_design.txt:187
WCMVContext::bpp
int bpp
Definition: wcmv.c:36
AVCodecContext
main external API structure.
Definition: avcodec.h:441
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:280
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
FFZStream
Definition: zlib_wrapper.h:27
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:468
AVPacket
This structure stores compressed data.
Definition: packet.h:468
ff_inflate_init
int ff_inflate_init(FFZStream *zstream, void *logctx)
Wrapper around inflateInit().
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:621
bytestream.h
imgutils.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
decode_close
static av_cold int decode_close(AVCodecContext *avctx)
Definition: wcmv.c:234
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
h
h
Definition: vp9dsp_template.c:2038
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: wcmv.c:212
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375
FF_REGET_BUFFER_FLAG_READONLY
#define FF_REGET_BUFFER_FLAG_READONLY
the returned buffer does not need to be writable
Definition: decode.h:128