Libav
motionpixels.c
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1 /*
2  * Motion Pixels Video Decoder
3  * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avcodec.h"
23 #include "get_bits.h"
24 #include "bswapdsp.h"
25 #include "internal.h"
26 
27 #define MAX_HUFF_CODES 16
28 
29 #include "motionpixels_tablegen.h"
30 
31 typedef struct HuffCode {
32  int code;
35 } HuffCode;
36 
37 typedef struct MotionPixelsContext {
52 
54 {
55  MotionPixelsContext *mp = avctx->priv_data;
56 
57  av_freep(&mp->changes_map);
58  av_freep(&mp->vpt);
59  av_freep(&mp->hpt);
60  av_freep(&mp->bswapbuf);
61  av_frame_free(&mp->frame);
62 
63  return 0;
64 }
65 
67 {
68  MotionPixelsContext *mp = avctx->priv_data;
69  int w4 = (avctx->width + 3) & ~3;
70  int h4 = (avctx->height + 3) & ~3;
71 
73  mp->avctx = avctx;
74  ff_bswapdsp_init(&mp->bdsp);
75  mp->changes_map = av_mallocz(avctx->width * h4);
76  mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
77  mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel));
78  mp->hpt = av_mallocz(h4 * w4 / 16 * sizeof(YuvPixel));
79  avctx->pix_fmt = AV_PIX_FMT_RGB555;
80 
81  mp->frame = av_frame_alloc();
82  if (!mp->frame) {
83  mp_decode_end(avctx);
84  return AVERROR(ENOMEM);
85  }
86 
87  return 0;
88 }
89 
90 static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
91 {
92  uint16_t *pixels;
93  int offset, w, h, color = 0, x, y, i;
94 
95  while (count--) {
96  offset = get_bits_long(gb, mp->offset_bits_len);
97  w = get_bits(gb, bits_len) + 1;
98  h = get_bits(gb, bits_len) + 1;
99  if (read_color)
100  color = get_bits(gb, 15);
101  x = offset % mp->avctx->width;
102  y = offset / mp->avctx->width;
103  if (y >= mp->avctx->height)
104  continue;
105  w = FFMIN(w, mp->avctx->width - x);
106  h = FFMIN(h, mp->avctx->height - y);
107  pixels = (uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
108  while (h--) {
109  mp->changes_map[offset] = w;
110  if (read_color)
111  for (i = 0; i < w; ++i)
112  pixels[i] = color;
113  offset += mp->avctx->width;
114  pixels += mp->frame->linesize[0] / 2;
115  }
116  }
117 }
118 
119 static void mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
120 {
121  while (get_bits1(gb)) {
122  ++size;
123  if (size > mp->max_codes_bits) {
124  av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
125  return;
126  }
127  code <<= 1;
128  mp_get_code(mp, gb, size, code + 1);
129  }
130  if (mp->current_codes_count >= MAX_HUFF_CODES) {
131  av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
132  return;
133  }
134  mp->codes[mp->current_codes_count ].code = code;
135  mp->codes[mp->current_codes_count++].size = size;
136 }
137 
139 {
140  if (mp->codes_count == 1) {
141  mp->codes[0].delta = get_bits(gb, 4);
142  } else {
143  int i;
144 
145  mp->max_codes_bits = get_bits(gb, 4);
146  for (i = 0; i < mp->codes_count; ++i)
147  mp->codes[i].delta = get_bits(gb, 4);
148  mp->current_codes_count = 0;
149  mp_get_code(mp, gb, 0, 0);
150  }
151 }
152 
153 static int mp_gradient(MotionPixelsContext *mp, int component, int v)
154 {
155  int delta;
156 
157  delta = (v - 7) * mp->gradient_scale[component];
158  mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
159  return delta;
160 }
161 
163 {
164  int color;
165 
166  color = *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
167  return mp_rgb_yuv_table[color];
168 }
169 
170 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
171 {
172  int color;
173 
174  color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
175  *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2] = color;
176 }
177 
179 {
180  int i;
181 
182  i = (mp->codes_count == 1) ? 0 : get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1);
183  i = FFMIN(i, FF_ARRAY_ELEMS(mp->codes) - 1);
184  return mp->codes[i].delta;
185 }
186 
188 {
189  YuvPixel p;
190  const int y0 = y * mp->avctx->width;
191  int w, i, x = 0;
192 
193  p = mp->vpt[y];
194  if (mp->changes_map[y0 + x] == 0) {
195  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
196  ++x;
197  }
198  while (x < mp->avctx->width) {
199  w = mp->changes_map[y0 + x];
200  if (w != 0) {
201  if ((y & 3) == 0) {
202  if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
203  mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
204  mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
205  for (i = (x + 3) & ~3; i < x + w; i += 4) {
206  mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
207  }
208  }
209  }
210  x += w;
211  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
212  p = mp_get_yuv_from_rgb(mp, x - 1, y);
213  } else {
214  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
215  p.y = av_clip(p.y, 0, 31);
216  if ((x & 3) == 0) {
217  if ((y & 3) == 0) {
218  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
219  p.v = av_clip(p.v, -32, 31);
220  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
221  p.u = av_clip(p.u, -32, 31);
222  mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
223  } else {
224  p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
225  p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
226  }
227  }
228  mp_set_rgb_from_yuv(mp, x, y, &p);
229  ++x;
230  }
231  }
232 }
233 
235 {
236  YuvPixel p;
237  int y, y0;
238 
239  for (y = 0; y < mp->avctx->height; ++y) {
240  if (mp->changes_map[y * mp->avctx->width] != 0) {
241  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
242  p = mp_get_yuv_from_rgb(mp, 0, y);
243  } else {
244  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
245  p.y = av_clip(p.y, 0, 31);
246  if ((y & 3) == 0) {
247  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
248  p.v = av_clip(p.v, -32, 31);
249  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
250  p.u = av_clip(p.u, -32, 31);
251  }
252  mp->vpt[y] = p;
253  mp_set_rgb_from_yuv(mp, 0, y, &p);
254  }
255  }
256  for (y0 = 0; y0 < 2; ++y0)
257  for (y = y0; y < mp->avctx->height; y += 2)
258  mp_decode_line(mp, gb, y);
259 }
260 
261 static int mp_decode_frame(AVCodecContext *avctx,
262  void *data, int *got_frame,
263  AVPacket *avpkt)
264 {
265  const uint8_t *buf = avpkt->data;
266  int buf_size = avpkt->size;
267  MotionPixelsContext *mp = avctx->priv_data;
268  GetBitContext gb;
269  int i, count1, count2, sz, ret;
270 
271  if ((ret = ff_reget_buffer(avctx, mp->frame)) < 0) {
272  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
273  return ret;
274  }
275 
276  /* le32 bitstream msb first */
278  if (!mp->bswapbuf)
279  return AVERROR(ENOMEM);
280  mp->bdsp.bswap_buf((uint32_t *) mp->bswapbuf, (const uint32_t *) buf,
281  buf_size / 4);
282  if (buf_size & 3)
283  memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
284  memset(mp->bswapbuf + buf_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
285  init_get_bits(&gb, mp->bswapbuf, buf_size * 8);
286 
287  memset(mp->changes_map, 0, avctx->width * avctx->height);
288  for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
289  count1 = get_bits(&gb, 12);
290  count2 = get_bits(&gb, 12);
291  mp_read_changes_map(mp, &gb, count1, 8, i);
292  mp_read_changes_map(mp, &gb, count2, 4, i);
293  }
294 
295  mp->codes_count = get_bits(&gb, 4);
296  if (mp->codes_count == 0)
297  goto end;
298 
299  if (mp->changes_map[0] == 0) {
300  *(uint16_t *)mp->frame->data[0] = get_bits(&gb, 15);
301  mp->changes_map[0] = 1;
302  }
303  mp_read_codes_table(mp, &gb);
304 
305  sz = get_bits(&gb, 18);
306  if (avctx->extradata[0] != 5)
307  sz += get_bits(&gb, 18);
308  if (sz == 0)
309  goto end;
310 
311  if (mp->max_codes_bits <= 0)
312  goto end;
313  if (init_vlc(&mp->vlc, mp->max_codes_bits, mp->codes_count, &mp->codes[0].size, sizeof(HuffCode), 1, &mp->codes[0].code, sizeof(HuffCode), 4, 0))
314  goto end;
315  mp_decode_frame_helper(mp, &gb);
316  ff_free_vlc(&mp->vlc);
317 
318 end:
319  if ((ret = av_frame_ref(data, mp->frame)) < 0)
320  return ret;
321  *got_frame = 1;
322  return buf_size;
323 }
324 
326  .name = "motionpixels",
327  .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
328  .type = AVMEDIA_TYPE_VIDEO,
330  .priv_data_size = sizeof(MotionPixelsContext),
331  .init = mp_decode_init,
332  .close = mp_decode_end,
334  .capabilities = CODEC_CAP_DR1,
335 };
int size
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
uint8_t size
Definition: motionpixels.c:33
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:240
AVCodec ff_motionpixels_decoder
Definition: motionpixels.c:325
int size
Definition: avcodec.h:974
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1254
#define FF_ARRAY_ELEMS(a)
AVCodec.
Definition: avcodec.h:2796
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
uint8_t delta
Definition: motionpixels.c:34
uint8_t
#define av_cold
Definition: attributes.h:66
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
float delta
void(* bswap_buf)(uint32_t *dst, const uint32_t *src, int w)
Definition: bswapdsp.h:25
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:188
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1164
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
Definition: motionpixels.c:162
uint8_t * data
Definition: avcodec.h:973
bitstream reader API header.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:69
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
const char * name
Name of the codec implementation.
Definition: avcodec.h:2803
BswapDSPContext bdsp
Definition: motionpixels.c:40
Definition: get_bits.h:64
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:531
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: utils.c:808
#define FFMIN(a, b)
Definition: common.h:57
static int mp_yuv_to_rgb(int y, int v, int u, int clip_rgb)
int width
picture width / height.
Definition: avcodec.h:1224
AVCodecContext * avctx
Definition: motionpixels.c:38
static int mp_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: motionpixels.c:261
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE(*table)[2], int bits, int max_depth)
Parse a vlc code.
Definition: get_bits.h:522
uint8_t * changes_map
Definition: motionpixels.c:41
static void mp_decode_frame_helper(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:234
static av_cold int mp_decode_init(AVCodecContext *avctx)
Definition: motionpixels.c:66
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:153
main external API structure.
Definition: avcodec.h:1050
HuffCode codes[MAX_HUFF_CODES]
Definition: motionpixels.c:45
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
#define init_vlc(vlc, nb_bits, nb_codes,bits, bits_wrap, bits_size,codes, codes_wrap, codes_size,flags)
Definition: get_bits.h:424
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:271
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:375
static int mp_gradient(MotionPixelsContext *mp, int component, int v)
Definition: motionpixels.c:153
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:304
static int mp_get_vlc(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:178
uint8_t gradient_scale[3]
Definition: motionpixels.c:48
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
static void mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
Definition: motionpixels.c:119
static void mp_decode_line(MotionPixelsContext *mp, GetBitContext *gb, int y)
Definition: motionpixels.c:187
void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
Allocate a buffer, reusing the given one if large enough.
Definition: mem.c:388
common internal api header.
static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
Definition: motionpixels.c:90
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:231
static const uint8_t color[]
Definition: log.c:55
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
#define MAX_HUFF_CODES
Definition: motionpixels.c:27
void * priv_data
Definition: avcodec.h:1092
static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
Definition: motionpixels.c:170
static av_cold int mp_decode_end(AVCodecContext *avctx)
Definition: motionpixels.c:53
#define av_log2
Definition: intmath.h:85
VLC_TYPE(* table)[2]
code, bits
Definition: get_bits.h:66
static YuvPixel mp_rgb_yuv_table[1<< 15]
static void mp_read_codes_table(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:138
static void motionpixels_tableinit(void)
This structure stores compressed data.
Definition: avcodec.h:950
void ff_free_vlc(VLC *vlc)
Definition: bitstream.c:333
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:205