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msvideo1.c
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1 /*
2  * Microsoft Video-1 Decoder
3  * Copyright (C) 2003 The FFmpeg project
4  *
5  * This file is part of FFmpeg.
6  *
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.
11  *
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.
16  *
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
20  */
21 
22 /**
23  * @file
24  * Microsoft Video-1 Decoder by Mike Melanson (melanson@pcisys.net)
25  * For more information about the MS Video-1 format, visit:
26  * http://www.pcisys.net/~melanson/codecs/
27  */
28 
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 
33 #include "libavutil/internal.h"
34 #include "libavutil/intreadwrite.h"
35 #include "avcodec.h"
36 #include "internal.h"
37 
38 #define PALETTE_COUNT 256
39 #define CHECK_STREAM_PTR(n) \
40  if ((stream_ptr + n) > s->size ) { \
41  av_log(s->avctx, AV_LOG_ERROR, " MS Video-1 warning: stream_ptr out of bounds (%d >= %d)\n", \
42  stream_ptr + n, s->size); \
43  return; \
44  }
45 
46 typedef struct Msvideo1Context {
47 
50 
51  const unsigned char *buf;
52  int size;
53 
54  int mode_8bit; /* if it's not 8-bit, it's 16-bit */
55 
56  uint32_t pal[256];
58 
60 {
61  Msvideo1Context *s = avctx->priv_data;
62 
63  s->avctx = avctx;
64 
65  if (avctx->width < 4 || avctx->height < 4)
66  return AVERROR_INVALIDDATA;
67 
68  /* figure out the colorspace based on the presence of a palette */
69  if (s->avctx->bits_per_coded_sample == 8) {
70  s->mode_8bit = 1;
71  avctx->pix_fmt = AV_PIX_FMT_PAL8;
72  if (avctx->extradata_size >= AVPALETTE_SIZE)
73  memcpy(s->pal, avctx->extradata, AVPALETTE_SIZE);
74  } else {
75  s->mode_8bit = 0;
76  avctx->pix_fmt = AV_PIX_FMT_RGB555;
77  }
78 
79  s->frame = av_frame_alloc();
80  if (!s->frame)
81  return AVERROR(ENOMEM);
82 
83  return 0;
84 }
85 
87 {
88  int block_ptr, pixel_ptr;
89  int total_blocks;
90  int pixel_x, pixel_y; /* pixel width and height iterators */
91  int block_x, block_y; /* block width and height iterators */
92  int blocks_wide, blocks_high; /* width and height in 4x4 blocks */
93  int block_inc;
94  int row_dec;
95 
96  /* decoding parameters */
97  int stream_ptr;
98  unsigned char byte_a, byte_b;
99  unsigned short flags;
100  int skip_blocks;
101  unsigned char colors[8];
102  unsigned char *pixels = s->frame->data[0];
103  int stride = s->frame->linesize[0];
104 
105  stream_ptr = 0;
106  skip_blocks = 0;
107  blocks_wide = s->avctx->width / 4;
108  blocks_high = s->avctx->height / 4;
109  total_blocks = blocks_wide * blocks_high;
110  block_inc = 4;
111  row_dec = stride + 4;
112 
113  for (block_y = blocks_high; block_y > 0; block_y--) {
114  block_ptr = ((block_y * 4) - 1) * stride;
115  for (block_x = blocks_wide; block_x > 0; block_x--) {
116  /* check if this block should be skipped */
117  if (skip_blocks) {
118  block_ptr += block_inc;
119  skip_blocks--;
120  total_blocks--;
121  continue;
122  }
123 
124  pixel_ptr = block_ptr;
125 
126  /* get the next two bytes in the encoded data stream */
127  CHECK_STREAM_PTR(2);
128  byte_a = s->buf[stream_ptr++];
129  byte_b = s->buf[stream_ptr++];
130 
131  /* check if the decode is finished */
132  if ((byte_a == 0) && (byte_b == 0) && (total_blocks == 0))
133  return;
134  else if ((byte_b & 0xFC) == 0x84) {
135  /* skip code, but don't count the current block */
136  skip_blocks = ((byte_b - 0x84) << 8) + byte_a - 1;
137  } else if (byte_b < 0x80) {
138  /* 2-color encoding */
139  flags = (byte_b << 8) | byte_a;
140 
141  CHECK_STREAM_PTR(2);
142  colors[0] = s->buf[stream_ptr++];
143  colors[1] = s->buf[stream_ptr++];
144 
145  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
146  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
147  pixels[pixel_ptr++] = colors[(flags & 0x1) ^ 1];
148  pixel_ptr -= row_dec;
149  }
150  } else if (byte_b >= 0x90) {
151  /* 8-color encoding */
152  flags = (byte_b << 8) | byte_a;
153 
154  CHECK_STREAM_PTR(8);
155  memcpy(colors, &s->buf[stream_ptr], 8);
156  stream_ptr += 8;
157 
158  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
159  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
160  pixels[pixel_ptr++] =
161  colors[((pixel_y & 0x2) << 1) +
162  (pixel_x & 0x2) + ((flags & 0x1) ^ 1)];
163  pixel_ptr -= row_dec;
164  }
165  } else {
166  /* 1-color encoding */
167  colors[0] = byte_a;
168 
169  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
170  for (pixel_x = 0; pixel_x < 4; pixel_x++)
171  pixels[pixel_ptr++] = colors[0];
172  pixel_ptr -= row_dec;
173  }
174  }
175 
176  block_ptr += block_inc;
177  total_blocks--;
178  }
179  }
180 
181  /* make the palette available on the way out */
182  if (s->avctx->pix_fmt == AV_PIX_FMT_PAL8)
183  memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
184 }
185 
187 {
188  int block_ptr, pixel_ptr;
189  int total_blocks;
190  int pixel_x, pixel_y; /* pixel width and height iterators */
191  int block_x, block_y; /* block width and height iterators */
192  int blocks_wide, blocks_high; /* width and height in 4x4 blocks */
193  int block_inc;
194  int row_dec;
195 
196  /* decoding parameters */
197  int stream_ptr;
198  unsigned char byte_a, byte_b;
199  unsigned short flags;
200  int skip_blocks;
201  unsigned short colors[8];
202  unsigned short *pixels = (unsigned short *)s->frame->data[0];
203  int stride = s->frame->linesize[0] / 2;
204 
205  stream_ptr = 0;
206  skip_blocks = 0;
207  blocks_wide = s->avctx->width / 4;
208  blocks_high = s->avctx->height / 4;
209  total_blocks = blocks_wide * blocks_high;
210  block_inc = 4;
211  row_dec = stride + 4;
212 
213  for (block_y = blocks_high; block_y > 0; block_y--) {
214  block_ptr = ((block_y * 4) - 1) * stride;
215  for (block_x = blocks_wide; block_x > 0; block_x--) {
216  /* check if this block should be skipped */
217  if (skip_blocks) {
218  block_ptr += block_inc;
219  skip_blocks--;
220  total_blocks--;
221  continue;
222  }
223 
224  pixel_ptr = block_ptr;
225 
226  /* get the next two bytes in the encoded data stream */
227  CHECK_STREAM_PTR(2);
228  byte_a = s->buf[stream_ptr++];
229  byte_b = s->buf[stream_ptr++];
230 
231  /* check if the decode is finished */
232  if ((byte_a == 0) && (byte_b == 0) && (total_blocks == 0)) {
233  return;
234  } else if ((byte_b & 0xFC) == 0x84) {
235  /* skip code, but don't count the current block */
236  skip_blocks = ((byte_b - 0x84) << 8) + byte_a - 1;
237  } else if (byte_b < 0x80) {
238  /* 2- or 8-color encoding modes */
239  flags = (byte_b << 8) | byte_a;
240 
241  CHECK_STREAM_PTR(4);
242  colors[0] = AV_RL16(&s->buf[stream_ptr]);
243  stream_ptr += 2;
244  colors[1] = AV_RL16(&s->buf[stream_ptr]);
245  stream_ptr += 2;
246 
247  if (colors[0] & 0x8000) {
248  /* 8-color encoding */
249  CHECK_STREAM_PTR(12);
250  colors[2] = AV_RL16(&s->buf[stream_ptr]);
251  stream_ptr += 2;
252  colors[3] = AV_RL16(&s->buf[stream_ptr]);
253  stream_ptr += 2;
254  colors[4] = AV_RL16(&s->buf[stream_ptr]);
255  stream_ptr += 2;
256  colors[5] = AV_RL16(&s->buf[stream_ptr]);
257  stream_ptr += 2;
258  colors[6] = AV_RL16(&s->buf[stream_ptr]);
259  stream_ptr += 2;
260  colors[7] = AV_RL16(&s->buf[stream_ptr]);
261  stream_ptr += 2;
262 
263  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
264  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
265  pixels[pixel_ptr++] =
266  colors[((pixel_y & 0x2) << 1) +
267  (pixel_x & 0x2) + ((flags & 0x1) ^ 1)];
268  pixel_ptr -= row_dec;
269  }
270  } else {
271  /* 2-color encoding */
272  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
273  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
274  pixels[pixel_ptr++] = colors[(flags & 0x1) ^ 1];
275  pixel_ptr -= row_dec;
276  }
277  }
278  } else {
279  /* otherwise, it's a 1-color block */
280  colors[0] = (byte_b << 8) | byte_a;
281 
282  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
283  for (pixel_x = 0; pixel_x < 4; pixel_x++)
284  pixels[pixel_ptr++] = colors[0];
285  pixel_ptr -= row_dec;
286  }
287  }
288 
289  block_ptr += block_inc;
290  total_blocks--;
291  }
292  }
293 }
294 
296  void *data, int *got_frame,
297  AVPacket *avpkt)
298 {
299  const uint8_t *buf = avpkt->data;
300  int buf_size = avpkt->size;
301  Msvideo1Context *s = avctx->priv_data;
302  int ret;
303 
304  s->buf = buf;
305  s->size = buf_size;
306 
307  // Discard frame if its smaller than the minimum frame size
308  if (buf_size < (avctx->width/4) * (avctx->height/4) / 512) {
309  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
310  return AVERROR_INVALIDDATA;
311  }
312 
313  if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
314  return ret;
315 
316  if (s->mode_8bit) {
317  int size;
318  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
319 
320  if (pal && size == AVPALETTE_SIZE) {
321  memcpy(s->pal, pal, AVPALETTE_SIZE);
322  s->frame->palette_has_changed = 1;
323  } else if (pal) {
324  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
325  }
326  }
327 
328  if (s->mode_8bit)
330  else
332 
333  if ((ret = av_frame_ref(data, s->frame)) < 0)
334  return ret;
335 
336  *got_frame = 1;
337 
338  /* report that the buffer was completely consumed */
339  return buf_size;
340 }
341 
343 {
344  Msvideo1Context *s = avctx->priv_data;
345 
346  av_frame_free(&s->frame);
347 
348  return 0;
349 }
350 
352  .name = "msvideo1",
353  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Video 1"),
354  .type = AVMEDIA_TYPE_VIDEO,
355  .id = AV_CODEC_ID_MSVIDEO1,
356  .priv_data_size = sizeof(Msvideo1Context),
358  .close = msvideo1_decode_end,
360  .capabilities = AV_CODEC_CAP_DR1,
361 };
uint32_t pal[256]
Definition: msvideo1.c:56
static int msvideo1_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: msvideo1.c:295
#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:226
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
AVCodecContext * avctx
Definition: msvideo1.c:48
int size
Definition: avcodec.h:1453
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1750
AVCodec.
Definition: avcodec.h:3441
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: decode.c:1965
static av_cold int msvideo1_decode_end(AVCodecContext *avctx)
Definition: msvideo1.c:342
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
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
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 * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1641
uint8_t * data
Definition: avcodec.h:1452
ptrdiff_t size
Definition: opengl_enc.c:101
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2760
#define av_log(a,...)
const unsigned char * buf
Definition: msvideo1.c:51
#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:1165
#define AVERROR(e)
Definition: error.h:43
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
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
const char * name
Name of the codec implementation.
Definition: avcodec.h:3448
AVCodec ff_msvideo1_decoder
Definition: msvideo1.c:351
static void msvideo1_decode_16bit(Msvideo1Context *s)
Definition: msvideo1.c:186
common internal API header
int width
picture width / height.
Definition: avcodec.h:1713
#define s(width, name)
Definition: cbs_vp9.c:257
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:257
main external API structure.
Definition: avcodec.h:1540
void * buf
Definition: avisynth_c.h:690
int extradata_size
Definition: avcodec.h:1642
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:383
static void msvideo1_decode_8bit(Msvideo1Context *s)
Definition: msvideo1.c:86
#define CHECK_STREAM_PTR(n)
Definition: msvideo1.c:39
AVFrame * frame
Definition: msvideo1.c:49
#define flags(name, subs,...)
Definition: cbs_av1.c:584
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:240
static av_cold int msvideo1_decode_init(AVCodecContext *avctx)
Definition: msvideo1.c:59
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
common internal api header.
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:372
void * priv_data
Definition: avcodec.h:1567
int pixels
Definition: avisynth_c.h:429
#define stride
This structure stores compressed data.
Definition: avcodec.h:1429
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:968
for(j=16;j >0;--j)