FFmpeg
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 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 #include "libavutil/thread.h"
23 
24 #include "config.h"
25 
26 #include "avcodec.h"
27 #include "get_bits.h"
28 #include "bswapdsp.h"
29 #include "internal.h"
30 
31 #define MAX_HUFF_CODES 16
32 
33 #include "motionpixels_tablegen.h"
34 
35 typedef struct HuffCode {
38 } HuffCode;
39 
40 typedef struct MotionPixelsContext {
46  int codes_count, current_codes_count;
50  YuvPixel *vpt, *hpt;
51  uint8_t gradient_scale[3];
55 
57 {
58  MotionPixelsContext *mp = avctx->priv_data;
59 
60  av_freep(&mp->changes_map);
61  av_freep(&mp->vpt);
62  av_freep(&mp->hpt);
63  av_freep(&mp->bswapbuf);
64  av_frame_free(&mp->frame);
65 
66  return 0;
67 }
68 
70 {
71  av_unused static AVOnce init_static_once = AV_ONCE_INIT;
72  MotionPixelsContext *mp = avctx->priv_data;
73  int w4 = (avctx->width + 3) & ~3;
74  int h4 = (avctx->height + 3) & ~3;
75 
76  if(avctx->extradata_size < 2){
77  av_log(avctx, AV_LOG_ERROR, "extradata too small\n");
78  return AVERROR_INVALIDDATA;
79  }
80 
81  mp->avctx = avctx;
82  ff_bswapdsp_init(&mp->bdsp);
83  mp->changes_map = av_mallocz_array(avctx->width, h4);
84  mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
85  mp->vpt = av_mallocz_array(avctx->height, sizeof(YuvPixel));
86  mp->hpt = av_mallocz_array(h4 / 4, w4 / 4 * sizeof(YuvPixel));
87  if (!mp->changes_map || !mp->vpt || !mp->hpt)
88  return AVERROR(ENOMEM);
89  avctx->pix_fmt = AV_PIX_FMT_RGB555;
90 
91  mp->frame = av_frame_alloc();
92  if (!mp->frame)
93  return AVERROR(ENOMEM);
94 
95 #if !CONFIG_HARDCODED_TABLES
96  ff_thread_once(&init_static_once, motionpixels_tableinit);
97 #endif
98 
99  return 0;
100 }
101 
102 static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
103 {
104  uint16_t *pixels;
105  int offset, w, h, color = 0, x, y, i;
106 
107  while (count--) {
108  offset = get_bits_long(gb, mp->offset_bits_len);
109  w = get_bits(gb, bits_len) + 1;
110  h = get_bits(gb, bits_len) + 1;
111  if (read_color)
112  color = get_bits(gb, 15);
113  x = offset % mp->avctx->width;
114  y = offset / mp->avctx->width;
115  if (y >= mp->avctx->height)
116  continue;
117  w = FFMIN(w, mp->avctx->width - x);
118  h = FFMIN(h, mp->avctx->height - y);
119  pixels = (uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
120  while (h--) {
121  mp->changes_map[offset] = w;
122  if (read_color)
123  for (i = 0; i < w; ++i)
124  pixels[i] = color;
125  offset += mp->avctx->width;
126  pixels += mp->frame->linesize[0] / 2;
127  }
128  }
129 }
130 
132 {
133  while (get_bits1(gb)) {
134  ++size;
135  if (size > mp->max_codes_bits) {
136  av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
137  return AVERROR_INVALIDDATA;
138  }
139  if (mp_get_code(mp, gb, size) < 0)
140  return AVERROR_INVALIDDATA;
141  }
142  if (mp->current_codes_count >= mp->codes_count) {
143  av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
144  return AVERROR_INVALIDDATA;
145  }
146 
147  mp->codes[mp->current_codes_count++].size = size;
148  return 0;
149 }
150 
152 {
153  if (mp->codes_count == 1) {
154  mp->codes[0].delta = get_bits(gb, 4);
155  } else {
156  int i;
157  int ret;
158 
159  mp->max_codes_bits = get_bits(gb, 4);
160  for (i = 0; i < mp->codes_count; ++i)
161  mp->codes[i].delta = get_bits(gb, 4);
162  mp->current_codes_count = 0;
163  if ((ret = mp_get_code(mp, gb, 0)) < 0)
164  return ret;
165  if (mp->current_codes_count < mp->codes_count) {
166  av_log(mp->avctx, AV_LOG_ERROR, "too few codes\n");
167  return AVERROR_INVALIDDATA;
168  }
169  }
170  return 0;
171 }
172 
173 static av_always_inline int mp_gradient(MotionPixelsContext *mp, int component, int v)
174 {
175  int delta;
176 
177  delta = (v - 7) * mp->gradient_scale[component];
178  mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
179  return delta;
180 }
181 
183 {
184  int color;
185 
186  color = *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
187  return mp_rgb_yuv_table[color];
188 }
189 
190 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
191 {
192  int color;
193 
194  color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
195  *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2] = color;
196 }
197 
199 {
200  return mp->vlc.table ? get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1)
201  : mp->codes[0].delta;
202 }
203 
205 {
206  YuvPixel p;
207  const int y0 = y * mp->avctx->width;
208  int w, i, x = 0;
209 
210  p = mp->vpt[y];
211  if (mp->changes_map[y0 + x] == 0) {
212  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
213  ++x;
214  }
215  while (x < mp->avctx->width) {
216  w = mp->changes_map[y0 + x];
217  if (w != 0) {
218  if ((y & 3) == 0) {
219  if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
220  mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
221  mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
222  for (i = (x + 3) & ~3; i < x + w; i += 4) {
223  mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
224  }
225  }
226  }
227  x += w;
228  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
229  p = mp_get_yuv_from_rgb(mp, x - 1, y);
230  } else {
231  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
232  p.y = av_clip_uintp2(p.y, 5);
233  if ((x & 3) == 0) {
234  if ((y & 3) == 0) {
235  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
236  p.v = av_clip_intp2(p.v, 5);
237  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
238  p.u = av_clip_intp2(p.u, 5);
239  mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
240  } else {
241  p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
242  p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
243  }
244  }
245  mp_set_rgb_from_yuv(mp, x, y, &p);
246  ++x;
247  }
248  }
249 }
250 
252 {
253  YuvPixel p;
254  int y, y0;
255 
256  av_assert1(mp->changes_map[0]);
257 
258  for (y = 0; y < mp->avctx->height; ++y) {
259  if (mp->changes_map[y * mp->avctx->width] != 0) {
260  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
261  p = mp_get_yuv_from_rgb(mp, 0, y);
262  } else {
263  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
264  p.y = av_clip_uintp2(p.y, 5);
265  if ((y & 3) == 0) {
266  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
267  p.v = av_clip_intp2(p.v, 5);
268  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
269  p.u = av_clip_intp2(p.u, 5);
270  }
271  mp->vpt[y] = p;
272  mp_set_rgb_from_yuv(mp, 0, y, &p);
273  }
274  }
275  for (y0 = 0; y0 < 2; ++y0)
276  for (y = y0; y < mp->avctx->height; y += 2)
277  mp_decode_line(mp, gb, y);
278 }
279 
280 static int mp_decode_frame(AVCodecContext *avctx,
281  void *data, int *got_frame,
282  AVPacket *avpkt)
283 {
284  const uint8_t *buf = avpkt->data;
285  int buf_size = avpkt->size;
286  MotionPixelsContext *mp = avctx->priv_data;
287  GetBitContext gb;
288  int i, count1, count2, sz, ret;
289 
290  if ((ret = ff_reget_buffer(avctx, mp->frame, 0)) < 0)
291  return ret;
292 
293  /* le32 bitstream msb first */
294  av_fast_padded_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size);
295  if (!mp->bswapbuf)
296  return AVERROR(ENOMEM);
297  mp->bdsp.bswap_buf((uint32_t *) mp->bswapbuf, (const uint32_t *) buf,
298  buf_size / 4);
299  if (buf_size & 3)
300  memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
301  init_get_bits(&gb, mp->bswapbuf, buf_size * 8);
302 
303  memset(mp->changes_map, 0, avctx->width * avctx->height);
304  for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
305  count1 = get_bits(&gb, 12);
306  count2 = get_bits(&gb, 12);
307  mp_read_changes_map(mp, &gb, count1, 8, i);
308  mp_read_changes_map(mp, &gb, count2, 4, i);
309  }
310 
311  mp->codes_count = get_bits(&gb, 4);
312  if (mp->codes_count == 0)
313  goto end;
314 
315  if (mp->changes_map[0] == 0) {
316  *(uint16_t *)mp->frame->data[0] = get_bits(&gb, 15);
317  mp->changes_map[0] = 1;
318  }
319  if (mp_read_codes_table(mp, &gb) < 0)
320  goto end;
321 
322  sz = get_bits(&gb, 18);
323  if (avctx->extradata[0] != 5)
324  sz += get_bits(&gb, 18);
325  if (sz == 0)
326  goto end;
327 
328  if (mp->codes_count > 1) {
329  /* The entries of the mp->codes array are sorted from right to left
330  * in the Huffman tree, hence -(int)sizeof(HuffCode). */
332  &mp->codes[mp->codes_count - 1].size, -(int)sizeof(HuffCode),
333  &mp->codes[mp->codes_count - 1].delta, -(int)sizeof(HuffCode), 1,
334  0, 0, avctx);
335  if (ret < 0)
336  goto end;
337  }
338  mp_decode_frame_helper(mp, &gb);
339  ff_free_vlc(&mp->vlc);
340 
341 end:
342  if ((ret = av_frame_ref(data, mp->frame)) < 0)
343  return ret;
344  *got_frame = 1;
345  return buf_size;
346 }
347 
349  .name = "motionpixels",
350  .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
351  .type = AVMEDIA_TYPE_VIDEO,
353  .priv_data_size = sizeof(MotionPixelsContext),
354  .init = mp_decode_init,
355  .close = mp_decode_end,
357  .capabilities = AV_CODEC_CAP_DR1,
359 };
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:48
#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:314
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
uint8_t size
Definition: motionpixels.c:36
static int mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size)
Definition: motionpixels.c:131
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
AVCodec ff_motionpixels_decoder
Definition: motionpixels.c:348
int size
Definition: packet.h:364
int av_log2(unsigned v)
Definition: intmath.c:26
static av_always_inline int mp_gradient(MotionPixelsContext *mp, int component, int v)
Definition: motionpixels.c:173
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:741
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:72
AVCodec.
Definition: codec.h:190
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:40
uint8_t delta
Definition: motionpixels.c:37
uint8_t
#define av_cold
Definition: attributes.h:88
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
static const uint32_t color[16+AV_CLASS_CATEGORY_NB]
Definition: log.c:92
void(* bswap_buf)(uint32_t *dst, const uint32_t *src, int w)
Definition: bswapdsp.h:25
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
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:632
static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
Definition: motionpixels.c:182
uint8_t * data
Definition: packet.h:363
bitstream reader API header.
ptrdiff_t size
Definition: opengl_enc.c:100
#define AVOnce
Definition: thread.h:172
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:115
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:1983
const char * name
Name of the codec implementation.
Definition: codec.h:197
GLsizei count
Definition: opengl_enc.c:108
BswapDSPContext bdsp
Definition: motionpixels.c:43
Definition: vlc.h:26
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
#define FFMIN(a, b)
Definition: common.h:96
static int mp_yuv_to_rgb(int y, int v, int u, int clip_rgb)
int width
picture width / height.
Definition: avcodec.h:704
uint8_t w
Definition: llviddspenc.c:39
AVCodecContext * avctx
Definition: motionpixels.c:41
static int mp_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: motionpixels.c:280
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:797
static av_cold void motionpixels_tableinit(void)
uint8_t * changes_map
Definition: motionpixels.c:44
static void mp_decode_frame_helper(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:251
#define AV_ONCE_INIT
Definition: thread.h:173
static av_cold int mp_decode_init(AVCodecContext *avctx)
Definition: motionpixels.c:69
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:345
main external API structure.
Definition: avcodec.h:531
HuffCode codes[MAX_HUFF_CODES]
Definition: motionpixels.c:48
int extradata_size
Definition: avcodec.h:633
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
int ff_init_vlc_from_lengths(VLC *vlc_arg, int nb_bits, int nb_codes, const int8_t *lens, int lens_wrap, const void *symbols, int symbols_wrap, int symbols_size, int offset, int flags, void *logctx)
Build VLC decoding tables suitable for use with get_vlc2()
Definition: bitstream.c:381
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
static av_always_inline int mp_get_vlc(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:198
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:546
uint8_t gradient_scale[3]
Definition: motionpixels.c:51
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:328
static void mp_decode_line(MotionPixelsContext *mp, GetBitContext *gb, int y)
Definition: motionpixels.c:204
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:102
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:387
#define MAX_HUFF_CODES
Definition: motionpixels.c:31
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
void * priv_data
Definition: avcodec.h:558
static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
Definition: motionpixels.c:190
static av_cold int mp_decode_end(AVCodecContext *avctx)
Definition: motionpixels.c:56
static int ff_thread_once(char *control, void(*routine)(void))
Definition: thread.h:175
VLC_TYPE(* table)[2]
code, bits
Definition: vlc.h:28
static int mp_read_codes_table(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:151
static YuvPixel mp_rgb_yuv_table[1<< 15]
#define av_freep(p)
#define av_always_inline
Definition: attributes.h:45
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
This structure stores compressed data.
Definition: packet.h:340
void ff_free_vlc(VLC *vlc)
Definition: bitstream.c:431
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:50
int i
Definition: input.c:407
#define av_unused
Definition: attributes.h:131
void * av_mallocz_array(size_t nmemb, size_t size)
Definition: mem.c:190