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 
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 
34 #include "libavutil/internal.h"
35 #include "libavutil/intreadwrite.h"
36 #include "avcodec.h"
37 #include "internal.h"
38 
39 #define PALETTE_COUNT 256
40 #define CHECK_STREAM_PTR(n) \
41  if ((stream_ptr + n) > s->size ) { \
42  av_log(s->avctx, AV_LOG_ERROR, " MS Video-1 warning: stream_ptr out of bounds (%d >= %d)\n", \
43  stream_ptr + n, s->size); \
44  return; \
45  }
46 
47 typedef struct Msvideo1Context {
48 
51 
52  const unsigned char *buf;
53  int size;
54 
55  int mode_8bit; /* if it's not 8-bit, it's 16-bit */
56 
57  uint32_t pal[256];
59 
61 {
62  Msvideo1Context *s = avctx->priv_data;
63 
64  s->avctx = avctx;
65 
66  /* figure out the colorspace based on the presence of a palette */
67  if (s->avctx->bits_per_coded_sample == 8) {
68  s->mode_8bit = 1;
69  avctx->pix_fmt = AV_PIX_FMT_PAL8;
70  } else {
71  s->mode_8bit = 0;
72  avctx->pix_fmt = AV_PIX_FMT_RGB555;
73  }
74 
76 
77  return 0;
78 }
79 
81 {
82  int block_ptr, pixel_ptr;
83  int total_blocks;
84  int pixel_x, pixel_y; /* pixel width and height iterators */
85  int block_x, block_y; /* block width and height iterators */
86  int blocks_wide, blocks_high; /* width and height in 4x4 blocks */
87  int block_inc;
88  int row_dec;
89 
90  /* decoding parameters */
91  int stream_ptr;
92  unsigned char byte_a, byte_b;
93  unsigned short flags;
94  int skip_blocks;
95  unsigned char colors[8];
96  unsigned char *pixels = s->frame.data[0];
97  int stride = s->frame.linesize[0];
98 
99  stream_ptr = 0;
100  skip_blocks = 0;
101  blocks_wide = s->avctx->width / 4;
102  blocks_high = s->avctx->height / 4;
103  total_blocks = blocks_wide * blocks_high;
104  block_inc = 4;
105  row_dec = stride + 4;
106 
107  for (block_y = blocks_high; block_y > 0; block_y--) {
108  block_ptr = ((block_y * 4) - 1) * stride;
109  for (block_x = blocks_wide; block_x > 0; block_x--) {
110  /* check if this block should be skipped */
111  if (skip_blocks) {
112  block_ptr += block_inc;
113  skip_blocks--;
114  total_blocks--;
115  continue;
116  }
117 
118  pixel_ptr = block_ptr;
119 
120  /* get the next two bytes in the encoded data stream */
121  CHECK_STREAM_PTR(2);
122  byte_a = s->buf[stream_ptr++];
123  byte_b = s->buf[stream_ptr++];
124 
125  /* check if the decode is finished */
126  if ((byte_a == 0) && (byte_b == 0) && (total_blocks == 0))
127  return;
128  else if ((byte_b & 0xFC) == 0x84) {
129  /* skip code, but don't count the current block */
130  skip_blocks = ((byte_b - 0x84) << 8) + byte_a - 1;
131  } else if (byte_b < 0x80) {
132  /* 2-color encoding */
133  flags = (byte_b << 8) | byte_a;
134 
135  CHECK_STREAM_PTR(2);
136  colors[0] = s->buf[stream_ptr++];
137  colors[1] = s->buf[stream_ptr++];
138 
139  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
140  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
141  pixels[pixel_ptr++] = colors[(flags & 0x1) ^ 1];
142  pixel_ptr -= row_dec;
143  }
144  } else if (byte_b >= 0x90) {
145  /* 8-color encoding */
146  flags = (byte_b << 8) | byte_a;
147 
148  CHECK_STREAM_PTR(8);
149  memcpy(colors, &s->buf[stream_ptr], 8);
150  stream_ptr += 8;
151 
152  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
153  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
154  pixels[pixel_ptr++] =
155  colors[((pixel_y & 0x2) << 1) +
156  (pixel_x & 0x2) + ((flags & 0x1) ^ 1)];
157  pixel_ptr -= row_dec;
158  }
159  } else {
160  /* 1-color encoding */
161  colors[0] = byte_a;
162 
163  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
164  for (pixel_x = 0; pixel_x < 4; pixel_x++)
165  pixels[pixel_ptr++] = colors[0];
166  pixel_ptr -= row_dec;
167  }
168  }
169 
170  block_ptr += block_inc;
171  total_blocks--;
172  }
173  }
174 
175  /* make the palette available on the way out */
176  if (s->avctx->pix_fmt == AV_PIX_FMT_PAL8)
177  memcpy(s->frame.data[1], s->pal, AVPALETTE_SIZE);
178 }
179 
181 {
182  int block_ptr, pixel_ptr;
183  int total_blocks;
184  int pixel_x, pixel_y; /* pixel width and height iterators */
185  int block_x, block_y; /* block width and height iterators */
186  int blocks_wide, blocks_high; /* width and height in 4x4 blocks */
187  int block_inc;
188  int row_dec;
189 
190  /* decoding parameters */
191  int stream_ptr;
192  unsigned char byte_a, byte_b;
193  unsigned short flags;
194  int skip_blocks;
195  unsigned short colors[8];
196  unsigned short *pixels = (unsigned short *)s->frame.data[0];
197  int stride = s->frame.linesize[0] / 2;
198 
199  stream_ptr = 0;
200  skip_blocks = 0;
201  blocks_wide = s->avctx->width / 4;
202  blocks_high = s->avctx->height / 4;
203  total_blocks = blocks_wide * blocks_high;
204  block_inc = 4;
205  row_dec = stride + 4;
206 
207  for (block_y = blocks_high; block_y > 0; block_y--) {
208  block_ptr = ((block_y * 4) - 1) * stride;
209  for (block_x = blocks_wide; block_x > 0; block_x--) {
210  /* check if this block should be skipped */
211  if (skip_blocks) {
212  block_ptr += block_inc;
213  skip_blocks--;
214  total_blocks--;
215  continue;
216  }
217 
218  pixel_ptr = block_ptr;
219 
220  /* get the next two bytes in the encoded data stream */
221  CHECK_STREAM_PTR(2);
222  byte_a = s->buf[stream_ptr++];
223  byte_b = s->buf[stream_ptr++];
224 
225  /* check if the decode is finished */
226  if ((byte_a == 0) && (byte_b == 0) && (total_blocks == 0)) {
227  return;
228  } else if ((byte_b & 0xFC) == 0x84) {
229  /* skip code, but don't count the current block */
230  skip_blocks = ((byte_b - 0x84) << 8) + byte_a - 1;
231  } else if (byte_b < 0x80) {
232  /* 2- or 8-color encoding modes */
233  flags = (byte_b << 8) | byte_a;
234 
235  CHECK_STREAM_PTR(4);
236  colors[0] = AV_RL16(&s->buf[stream_ptr]);
237  stream_ptr += 2;
238  colors[1] = AV_RL16(&s->buf[stream_ptr]);
239  stream_ptr += 2;
240 
241  if (colors[0] & 0x8000) {
242  /* 8-color encoding */
243  CHECK_STREAM_PTR(12);
244  colors[2] = AV_RL16(&s->buf[stream_ptr]);
245  stream_ptr += 2;
246  colors[3] = AV_RL16(&s->buf[stream_ptr]);
247  stream_ptr += 2;
248  colors[4] = AV_RL16(&s->buf[stream_ptr]);
249  stream_ptr += 2;
250  colors[5] = AV_RL16(&s->buf[stream_ptr]);
251  stream_ptr += 2;
252  colors[6] = AV_RL16(&s->buf[stream_ptr]);
253  stream_ptr += 2;
254  colors[7] = AV_RL16(&s->buf[stream_ptr]);
255  stream_ptr += 2;
256 
257  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
258  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
259  pixels[pixel_ptr++] =
260  colors[((pixel_y & 0x2) << 1) +
261  (pixel_x & 0x2) + ((flags & 0x1) ^ 1)];
262  pixel_ptr -= row_dec;
263  }
264  } else {
265  /* 2-color encoding */
266  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
267  for (pixel_x = 0; pixel_x < 4; pixel_x++, flags >>= 1)
268  pixels[pixel_ptr++] = colors[(flags & 0x1) ^ 1];
269  pixel_ptr -= row_dec;
270  }
271  }
272  } else {
273  /* otherwise, it's a 1-color block */
274  colors[0] = (byte_b << 8) | byte_a;
275 
276  for (pixel_y = 0; pixel_y < 4; pixel_y++) {
277  for (pixel_x = 0; pixel_x < 4; pixel_x++)
278  pixels[pixel_ptr++] = colors[0];
279  pixel_ptr -= row_dec;
280  }
281  }
282 
283  block_ptr += block_inc;
284  total_blocks--;
285  }
286  }
287 }
288 
290  void *data, int *got_frame,
291  AVPacket *avpkt)
292 {
293  const uint8_t *buf = avpkt->data;
294  int buf_size = avpkt->size;
295  Msvideo1Context *s = avctx->priv_data;
296  int ret;
297 
298  s->buf = buf;
299  s->size = buf_size;
300 
301  if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
302  return ret;
303 
304  if (s->mode_8bit) {
306 
307  if (pal) {
308  memcpy(s->pal, pal, AVPALETTE_SIZE);
309  s->frame.palette_has_changed = 1;
310  }
311  }
312 
313  if (s->mode_8bit)
315  else
317 
318  if ((ret = av_frame_ref(data, &s->frame)) < 0)
319  return ret;
320 
321  *got_frame = 1;
322 
323  /* report that the buffer was completely consumed */
324  return buf_size;
325 }
326 
328 {
329  Msvideo1Context *s = avctx->priv_data;
330 
331  av_frame_unref(&s->frame);
332 
333  return 0;
334 }
335 
337  .name = "msvideo1",
338  .type = AVMEDIA_TYPE_VIDEO,
339  .id = AV_CODEC_ID_MSVIDEO1,
340  .priv_data_size = sizeof(Msvideo1Context),
344  .capabilities = CODEC_CAP_DR1,
345  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Video 1"),
346 };
uint32_t pal[256]
Definition: msvideo1.c:57
static int msvideo1_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: msvideo1.c:289
const char * s
Definition: avisynth_c.h:668
This structure describes decoded (raw) audio or video data.
Definition: frame.h:76
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
AVCodecContext * avctx
Definition: msvideo1.c:49
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
#define AV_RL16
AVFrame frame
Definition: msvideo1.c:50
x1
Definition: genspecsines3.m:7
int stride
Definition: mace.c:144
static av_cold int msvideo1_decode_end(AVCodecContext *avctx)
Definition: msvideo1.c:327
uint8_t
#define av_cold
Definition: attributes.h:78
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:79
#define AVPALETTE_SIZE
Definition: pixfmt.h:33
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
uint8_t * data
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
const unsigned char * buf
Definition: msvideo1.c:52
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Spectrum Plot time data
const char * name
Name of the codec implementation.
external API header
AVCodec ff_msvideo1_decoder
Definition: msvideo1.c:336
static void msvideo1_decode_16bit(Msvideo1Context *s)
Definition: msvideo1.c:180
common internal API header
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...
ret
Definition: avfilter.c:821
int width
picture width / height.
NULL
Definition: eval.c:55
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:101
main external API structure.
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:375
void avcodec_get_frame_defaults(AVFrame *frame)
Set the fields of the given AVFrame to default values.
x2
Definition: genspecsines3.m:8
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:280
static void msvideo1_decode_8bit(Msvideo1Context *s)
Definition: msvideo1.c:80
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:330
#define CHECK_STREAM_PTR(n)
Definition: msvideo1.c:40
static int flags
Definition: cpu.c:23
int av_frame_ref(AVFrame *dst, AVFrame *src)
Setup a new reference to the data described by an given frame.
Definition: frame.c:228
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:87
static av_cold int msvideo1_decode_init(AVCodecContext *avctx)
Definition: msvideo1.c:60
common internal api header.
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:269
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:289
static int decode(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: crystalhd.c:868
This structure stores compressed data.
struct Msvideo1Context Msvideo1Context
for(j=16;j >0;--j)