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kmvc.c
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1 /*
2  * KMVC decoder
3  * Copyright (c) 2006 Konstantin Shishkov
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  * Karl Morton's Video Codec decoder
25  */
26 
27 #include <stdio.h>
28 #include <stdlib.h>
29 
30 #include "avcodec.h"
31 #include "bytestream.h"
32 #include "internal.h"
33 #include "libavutil/common.h"
34 
35 #define KMVC_KEYFRAME 0x80
36 #define KMVC_PALETTE 0x40
37 #define KMVC_METHOD 0x0F
38 #define MAX_PALSIZE 256
39 
40 /*
41  * Decoder context
42  */
43 typedef struct KmvcContext {
45 
46  int setpal;
47  int palsize;
48  uint32_t pal[MAX_PALSIZE];
50  uint8_t frm0[320 * 200], frm1[320 * 200];
52 } KmvcContext;
53 
54 typedef struct BitBuf {
55  int bits;
56  int bitbuf;
57 } BitBuf;
58 
59 #define BLK(data, x, y) data[av_clip((x) + (y) * 320, 0, 320 * 200 -1)]
60 
61 #define kmvc_init_getbits(bb, g) bb.bits = 7; bb.bitbuf = bytestream2_get_byte(g);
62 
63 #define kmvc_getbit(bb, g, res) {\
64  res = 0; \
65  if (bb.bitbuf & (1 << bb.bits)) res = 1; \
66  bb.bits--; \
67  if(bb.bits == -1) { \
68  bb.bitbuf = bytestream2_get_byte(g); \
69  bb.bits = 7; \
70  } \
71 }
72 
73 static int kmvc_decode_intra_8x8(KmvcContext * ctx, int w, int h)
74 {
75  BitBuf bb;
76  int res, val;
77  int i, j;
78  int bx, by;
79  int l0x, l1x, l0y, l1y;
80  int mx, my;
81 
82  kmvc_init_getbits(bb, &ctx->g);
83 
84  for (by = 0; by < h; by += 8)
85  for (bx = 0; bx < w; bx += 8) {
86  if (!bytestream2_get_bytes_left(&ctx->g)) {
87  av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n");
88  return AVERROR_INVALIDDATA;
89  }
90  kmvc_getbit(bb, &ctx->g, res);
91  if (!res) { // fill whole 8x8 block
92  val = bytestream2_get_byte(&ctx->g);
93  for (i = 0; i < 64; i++)
94  BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val;
95  } else { // handle four 4x4 subblocks
96  for (i = 0; i < 4; i++) {
97  l0x = bx + (i & 1) * 4;
98  l0y = by + (i & 2) * 2;
99  kmvc_getbit(bb, &ctx->g, res);
100  if (!res) {
101  kmvc_getbit(bb, &ctx->g, res);
102  if (!res) { // fill whole 4x4 block
103  val = bytestream2_get_byte(&ctx->g);
104  for (j = 0; j < 16; j++)
105  BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val;
106  } else { // copy block from already decoded place
107  val = bytestream2_get_byte(&ctx->g);
108  mx = val & 0xF;
109  my = val >> 4;
110  if ((l0x-mx) + 320*(l0y-my) < 0 || (l0x-mx) + 320*(l0y-my) > 320*197 - 4) {
111  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
112  return AVERROR_INVALIDDATA;
113  }
114  for (j = 0; j < 16; j++)
115  BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) =
116  BLK(ctx->cur, l0x + (j & 3) - mx, l0y + (j >> 2) - my);
117  }
118  } else { // descend to 2x2 sub-sub-blocks
119  for (j = 0; j < 4; j++) {
120  l1x = l0x + (j & 1) * 2;
121  l1y = l0y + (j & 2);
122  kmvc_getbit(bb, &ctx->g, res);
123  if (!res) {
124  kmvc_getbit(bb, &ctx->g, res);
125  if (!res) { // fill whole 2x2 block
126  val = bytestream2_get_byte(&ctx->g);
127  BLK(ctx->cur, l1x, l1y) = val;
128  BLK(ctx->cur, l1x + 1, l1y) = val;
129  BLK(ctx->cur, l1x, l1y + 1) = val;
130  BLK(ctx->cur, l1x + 1, l1y + 1) = val;
131  } else { // copy block from already decoded place
132  val = bytestream2_get_byte(&ctx->g);
133  mx = val & 0xF;
134  my = val >> 4;
135  if ((l1x-mx) + 320*(l1y-my) < 0 || (l1x-mx) + 320*(l1y-my) > 320*199 - 2) {
136  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
137  return AVERROR_INVALIDDATA;
138  }
139  BLK(ctx->cur, l1x, l1y) = BLK(ctx->cur, l1x - mx, l1y - my);
140  BLK(ctx->cur, l1x + 1, l1y) =
141  BLK(ctx->cur, l1x + 1 - mx, l1y - my);
142  BLK(ctx->cur, l1x, l1y + 1) =
143  BLK(ctx->cur, l1x - mx, l1y + 1 - my);
144  BLK(ctx->cur, l1x + 1, l1y + 1) =
145  BLK(ctx->cur, l1x + 1 - mx, l1y + 1 - my);
146  }
147  } else { // read values for block
148  BLK(ctx->cur, l1x, l1y) = bytestream2_get_byte(&ctx->g);
149  BLK(ctx->cur, l1x + 1, l1y) = bytestream2_get_byte(&ctx->g);
150  BLK(ctx->cur, l1x, l1y + 1) = bytestream2_get_byte(&ctx->g);
151  BLK(ctx->cur, l1x + 1, l1y + 1) = bytestream2_get_byte(&ctx->g);
152  }
153  }
154  }
155  }
156  }
157  }
158 
159  return 0;
160 }
161 
162 static int kmvc_decode_inter_8x8(KmvcContext * ctx, int w, int h)
163 {
164  BitBuf bb;
165  int res, val;
166  int i, j;
167  int bx, by;
168  int l0x, l1x, l0y, l1y;
169  int mx, my;
170 
171  kmvc_init_getbits(bb, &ctx->g);
172 
173  for (by = 0; by < h; by += 8)
174  for (bx = 0; bx < w; bx += 8) {
175  kmvc_getbit(bb, &ctx->g, res);
176  if (!res) {
177  kmvc_getbit(bb, &ctx->g, res);
178  if (!res) { // fill whole 8x8 block
179  if (!bytestream2_get_bytes_left(&ctx->g)) {
180  av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n");
181  return AVERROR_INVALIDDATA;
182  }
183  val = bytestream2_get_byte(&ctx->g);
184  for (i = 0; i < 64; i++)
185  BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val;
186  } else { // copy block from previous frame
187  for (i = 0; i < 64; i++)
188  BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) =
189  BLK(ctx->prev, bx + (i & 0x7), by + (i >> 3));
190  }
191  } else { // handle four 4x4 subblocks
192  if (!bytestream2_get_bytes_left(&ctx->g)) {
193  av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n");
194  return AVERROR_INVALIDDATA;
195  }
196  for (i = 0; i < 4; i++) {
197  l0x = bx + (i & 1) * 4;
198  l0y = by + (i & 2) * 2;
199  kmvc_getbit(bb, &ctx->g, res);
200  if (!res) {
201  kmvc_getbit(bb, &ctx->g, res);
202  if (!res) { // fill whole 4x4 block
203  val = bytestream2_get_byte(&ctx->g);
204  for (j = 0; j < 16; j++)
205  BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val;
206  } else { // copy block
207  val = bytestream2_get_byte(&ctx->g);
208  mx = (val & 0xF) - 8;
209  my = (val >> 4) - 8;
210  if ((l0x+mx) + 320*(l0y+my) < 0 || (l0x+mx) + 320*(l0y+my) > 320*197 - 4) {
211  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
212  return AVERROR_INVALIDDATA;
213  }
214  for (j = 0; j < 16; j++)
215  BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) =
216  BLK(ctx->prev, l0x + (j & 3) + mx, l0y + (j >> 2) + my);
217  }
218  } else { // descend to 2x2 sub-sub-blocks
219  for (j = 0; j < 4; j++) {
220  l1x = l0x + (j & 1) * 2;
221  l1y = l0y + (j & 2);
222  kmvc_getbit(bb, &ctx->g, res);
223  if (!res) {
224  kmvc_getbit(bb, &ctx->g, res);
225  if (!res) { // fill whole 2x2 block
226  val = bytestream2_get_byte(&ctx->g);
227  BLK(ctx->cur, l1x, l1y) = val;
228  BLK(ctx->cur, l1x + 1, l1y) = val;
229  BLK(ctx->cur, l1x, l1y + 1) = val;
230  BLK(ctx->cur, l1x + 1, l1y + 1) = val;
231  } else { // copy block
232  val = bytestream2_get_byte(&ctx->g);
233  mx = (val & 0xF) - 8;
234  my = (val >> 4) - 8;
235  if ((l1x+mx) + 320*(l1y+my) < 0 || (l1x+mx) + 320*(l1y+my) > 320*199 - 2) {
236  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
237  return AVERROR_INVALIDDATA;
238  }
239  BLK(ctx->cur, l1x, l1y) = BLK(ctx->prev, l1x + mx, l1y + my);
240  BLK(ctx->cur, l1x + 1, l1y) =
241  BLK(ctx->prev, l1x + 1 + mx, l1y + my);
242  BLK(ctx->cur, l1x, l1y + 1) =
243  BLK(ctx->prev, l1x + mx, l1y + 1 + my);
244  BLK(ctx->cur, l1x + 1, l1y + 1) =
245  BLK(ctx->prev, l1x + 1 + mx, l1y + 1 + my);
246  }
247  } else { // read values for block
248  BLK(ctx->cur, l1x, l1y) = bytestream2_get_byte(&ctx->g);
249  BLK(ctx->cur, l1x + 1, l1y) = bytestream2_get_byte(&ctx->g);
250  BLK(ctx->cur, l1x, l1y + 1) = bytestream2_get_byte(&ctx->g);
251  BLK(ctx->cur, l1x + 1, l1y + 1) = bytestream2_get_byte(&ctx->g);
252  }
253  }
254  }
255  }
256  }
257  }
258 
259  return 0;
260 }
261 
262 static int decode_frame(AVCodecContext * avctx, void *data, int *got_frame,
263  AVPacket *avpkt)
264 {
265  KmvcContext *const ctx = avctx->priv_data;
266  AVFrame *frame = data;
267  uint8_t *out, *src;
268  int i, ret;
269  int header;
270  int blocksize;
271  int pal_size;
272  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &pal_size);
273 
274  bytestream2_init(&ctx->g, avpkt->data, avpkt->size);
275 
276  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
277  return ret;
278 
279  header = bytestream2_get_byte(&ctx->g);
280 
281  /* blocksize 127 is really palette change event */
282  if (bytestream2_peek_byte(&ctx->g) == 127) {
283  bytestream2_skip(&ctx->g, 3);
284  for (i = 0; i < 127; i++) {
285  ctx->pal[i + (header & 0x81)] = 0xFFU << 24 | bytestream2_get_be24(&ctx->g);
286  bytestream2_skip(&ctx->g, 1);
287  }
288  bytestream2_seek(&ctx->g, -127 * 4 - 3, SEEK_CUR);
289  }
290 
291  if (header & KMVC_KEYFRAME) {
292  frame->key_frame = 1;
293  frame->pict_type = AV_PICTURE_TYPE_I;
294  } else {
295  frame->key_frame = 0;
296  frame->pict_type = AV_PICTURE_TYPE_P;
297  }
298 
299  if (header & KMVC_PALETTE) {
300  frame->palette_has_changed = 1;
301  // palette starts from index 1 and has 127 entries
302  for (i = 1; i <= ctx->palsize; i++) {
303  ctx->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&ctx->g);
304  }
305  }
306 
307  if (pal && pal_size == AVPALETTE_SIZE) {
308  frame->palette_has_changed = 1;
309  memcpy(ctx->pal, pal, AVPALETTE_SIZE);
310  } else if (pal) {
311  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", pal_size);
312  }
313 
314  if (ctx->setpal) {
315  ctx->setpal = 0;
316  frame->palette_has_changed = 1;
317  }
318 
319  /* make the palette available on the way out */
320  memcpy(frame->data[1], ctx->pal, 1024);
321 
322  blocksize = bytestream2_get_byte(&ctx->g);
323 
324  if (blocksize != 8 && blocksize != 127) {
325  av_log(avctx, AV_LOG_ERROR, "Block size = %i\n", blocksize);
326  return AVERROR_INVALIDDATA;
327  }
328  memset(ctx->cur, 0, 320 * 200);
329  switch (header & KMVC_METHOD) {
330  case 0:
331  case 1: // used in palette changed event
332  memcpy(ctx->cur, ctx->prev, 320 * 200);
333  break;
334  case 3:
335  kmvc_decode_intra_8x8(ctx, avctx->width, avctx->height);
336  break;
337  case 4:
338  kmvc_decode_inter_8x8(ctx, avctx->width, avctx->height);
339  break;
340  default:
341  av_log(avctx, AV_LOG_ERROR, "Unknown compression method %i\n", header & KMVC_METHOD);
342  return AVERROR_INVALIDDATA;
343  }
344 
345  out = frame->data[0];
346  src = ctx->cur;
347  for (i = 0; i < avctx->height; i++) {
348  memcpy(out, src, avctx->width);
349  src += 320;
350  out += frame->linesize[0];
351  }
352 
353  /* flip buffers */
354  if (ctx->cur == ctx->frm0) {
355  ctx->cur = ctx->frm1;
356  ctx->prev = ctx->frm0;
357  } else {
358  ctx->cur = ctx->frm0;
359  ctx->prev = ctx->frm1;
360  }
361 
362  *got_frame = 1;
363 
364  /* always report that the buffer was completely consumed */
365  return avpkt->size;
366 }
367 
368 
369 
370 /*
371  * Init kmvc decoder
372  */
373 static av_cold int decode_init(AVCodecContext * avctx)
374 {
375  KmvcContext *const c = avctx->priv_data;
376  int i;
377 
378  c->avctx = avctx;
379 
380  if (avctx->width > 320 || avctx->height > 200) {
381  av_log(avctx, AV_LOG_ERROR, "KMVC supports frames <= 320x200\n");
382  return AVERROR(EINVAL);
383  }
384 
385  c->cur = c->frm0;
386  c->prev = c->frm1;
387 
388  for (i = 0; i < 256; i++) {
389  c->pal[i] = 0xFFU << 24 | i * 0x10101;
390  }
391 
392  if (avctx->extradata_size < 12) {
393  av_log(avctx, AV_LOG_WARNING,
394  "Extradata missing, decoding may not work properly...\n");
395  c->palsize = 127;
396  } else {
397  c->palsize = AV_RL16(avctx->extradata + 10);
398  if (c->palsize >= (unsigned)MAX_PALSIZE) {
399  c->palsize = 127;
400  av_log(avctx, AV_LOG_ERROR, "KMVC palette too large\n");
401  return AVERROR_INVALIDDATA;
402  }
403  }
404 
405  if (avctx->extradata_size == 1036) { // palette in extradata
406  uint8_t *src = avctx->extradata + 12;
407  for (i = 0; i < 256; i++) {
408  c->pal[i] = AV_RL32(src);
409  src += 4;
410  }
411  c->setpal = 1;
412  }
413 
414  avctx->pix_fmt = AV_PIX_FMT_PAL8;
415 
416  return 0;
417 }
418 
420  .name = "kmvc",
421  .long_name = NULL_IF_CONFIG_SMALL("Karl Morton's video codec"),
422  .type = AVMEDIA_TYPE_VIDEO,
423  .id = AV_CODEC_ID_KMVC,
424  .priv_data_size = sizeof(KmvcContext),
425  .init = decode_init,
426  .decode = decode_frame,
427  .capabilities = AV_CODEC_CAP_DR1,
428 };
const char const char void * val
Definition: avisynth_c.h:771
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define MAX_PALSIZE
Definition: kmvc.c:38
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
GetByteContext g
Definition: kmvc.c:51
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1602
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1904
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
#define KMVC_PALETTE
Definition: kmvc.c:36
static int kmvc_decode_inter_8x8(KmvcContext *ctx, int w, int h)
Definition: kmvc.c:162
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3601
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
#define BLK(data, x, y)
Definition: kmvc.c:59
uint8_t
#define av_cold
Definition: attributes.h:82
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1791
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1601
AVCodecContext * avctx
Definition: kmvc.c:44
static const uint8_t header[24]
Definition: sdr2.c:67
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int palsize
Definition: kmvc.c:47
static int kmvc_decode_intra_8x8(KmvcContext *ctx, int w, int h)
Definition: kmvc.c:73
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
int bitbuf
Definition: kmvc.c:56
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:3608
#define kmvc_init_getbits(bb, g)
Definition: kmvc.c:61
int bits
Definition: kmvc.c:55
uint8_t frm1[320 *200]
Definition: kmvc.c:50
AVCodec ff_kmvc_decoder
Definition: kmvc.c:419
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:258
int width
picture width / height.
Definition: avcodec.h:1863
#define kmvc_getbit(bb, g, res)
Definition: kmvc.c:63
uint8_t frm0[320 *200]
Definition: kmvc.c:50
static av_cold int decode_init(AVCodecContext *avctx)
Definition: kmvc.c:373
AVFormatContext * ctx
Definition: movenc.c:48
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: kmvc.c:262
#define KMVC_METHOD
Definition: kmvc.c:37
int setpal
Definition: kmvc.c:46
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
main external API structure.
Definition: avcodec.h:1676
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:947
int extradata_size
Definition: avcodec.h:1792
Definition: kmvc.c:54
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:332
uint8_t * prev
Definition: kmvc.c:49
uint8_t * cur
Definition: kmvc.c:49
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
common internal api header.
common internal and external API header
#define KMVC_KEYFRAME
Definition: kmvc.c:35
void * priv_data
Definition: avcodec.h:1718
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:253
static AVCodec * c
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:208
FILE * out
Definition: movenc.c:54
static int decode(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *pkt)
Definition: ffmpeg.c:2045
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:339
uint32_t pal[MAX_PALSIZE]
Definition: kmvc.c:48
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1578
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:959
Predicted.
Definition: avutil.h:269