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 "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 {
43  int codes_count, current_codes_count;
47  YuvPixel *vpt, *hpt;
48  uint8_t gradient_scale[3];
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 
72  if(avctx->extradata_size < 2){
73  av_log(avctx, AV_LOG_ERROR, "extradata too small\n");
74  return AVERROR_INVALIDDATA;
75  }
76 
78  mp->avctx = avctx;
79  ff_bswapdsp_init(&mp->bdsp);
80  mp->changes_map = av_mallocz_array(avctx->width, h4);
81  mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
82  mp->vpt = av_mallocz_array(avctx->height, sizeof(YuvPixel));
83  mp->hpt = av_mallocz_array(h4 / 4, w4 / 4 * sizeof(YuvPixel));
84  if (!mp->changes_map || !mp->vpt || !mp->hpt)
85  return AVERROR(ENOMEM);
86  avctx->pix_fmt = AV_PIX_FMT_RGB555;
87 
88  mp->frame = av_frame_alloc();
89  if (!mp->frame)
90  return AVERROR(ENOMEM);
91 
92  return 0;
93 }
94 
95 static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
96 {
97  uint16_t *pixels;
98  int offset, w, h, color = 0, x, y, i;
99 
100  while (count--) {
101  offset = get_bits_long(gb, mp->offset_bits_len);
102  w = get_bits(gb, bits_len) + 1;
103  h = get_bits(gb, bits_len) + 1;
104  if (read_color)
105  color = get_bits(gb, 15);
106  x = offset % mp->avctx->width;
107  y = offset / mp->avctx->width;
108  if (y >= mp->avctx->height)
109  continue;
110  w = FFMIN(w, mp->avctx->width - x);
111  h = FFMIN(h, mp->avctx->height - y);
112  pixels = (uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
113  while (h--) {
114  mp->changes_map[offset] = w;
115  if (read_color)
116  for (i = 0; i < w; ++i)
117  pixels[i] = color;
118  offset += mp->avctx->width;
119  pixels += mp->frame->linesize[0] / 2;
120  }
121  }
122 }
123 
124 static int mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
125 {
126  while (get_bits1(gb)) {
127  ++size;
128  if (size > mp->max_codes_bits) {
129  av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
130  return AVERROR_INVALIDDATA;
131  }
132  code <<= 1;
133  if (mp_get_code(mp, gb, size, code + 1) < 0)
134  return AVERROR_INVALIDDATA;
135  }
136  if (mp->current_codes_count >= MAX_HUFF_CODES) {
137  av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  mp->codes[mp->current_codes_count ].code = code;
142  mp->codes[mp->current_codes_count++].size = size;
143  return 0;
144 }
145 
147 {
148  if (mp->codes_count == 1) {
149  mp->codes[0].delta = get_bits(gb, 4);
150  } else {
151  int i;
152  int ret;
153 
154  mp->max_codes_bits = get_bits(gb, 4);
155  for (i = 0; i < mp->codes_count; ++i)
156  mp->codes[i].delta = get_bits(gb, 4);
157  mp->current_codes_count = 0;
158  if ((ret = mp_get_code(mp, gb, 0, 0)) < 0)
159  return ret;
160  if (mp->current_codes_count < mp->codes_count) {
161  av_log(mp->avctx, AV_LOG_ERROR, "too few codes\n");
162  return AVERROR_INVALIDDATA;
163  }
164  }
165  return 0;
166 }
167 
168 static av_always_inline int mp_gradient(MotionPixelsContext *mp, int component, int v)
169 {
170  int delta;
171 
172  delta = (v - 7) * mp->gradient_scale[component];
173  mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
174  return delta;
175 }
176 
178 {
179  int color;
180 
181  color = *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
182  return mp_rgb_yuv_table[color];
183 }
184 
185 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
186 {
187  int color;
188 
189  color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
190  *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2] = color;
191 }
192 
194 {
195  int i;
196 
197  i = (mp->codes_count == 1) ? 0 : get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1);
198  if (i < 0)
199  return i;
200  return mp->codes[i].delta;
201 }
202 
204 {
205  YuvPixel p;
206  const int y0 = y * mp->avctx->width;
207  int w, i, x = 0;
208 
209  p = mp->vpt[y];
210  if (mp->changes_map[y0 + x] == 0) {
211  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
212  ++x;
213  }
214  while (x < mp->avctx->width) {
215  w = mp->changes_map[y0 + x];
216  if (w != 0) {
217  if ((y & 3) == 0) {
218  if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
219  mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
220  mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
221  for (i = (x + 3) & ~3; i < x + w; i += 4) {
222  mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
223  }
224  }
225  }
226  x += w;
227  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
228  p = mp_get_yuv_from_rgb(mp, x - 1, y);
229  } else {
230  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
231  p.y = av_clip_uintp2(p.y, 5);
232  if ((x & 3) == 0) {
233  if ((y & 3) == 0) {
234  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
235  p.v = av_clip_intp2(p.v, 5);
236  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
237  p.u = av_clip_intp2(p.u, 5);
238  mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
239  } else {
240  p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
241  p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
242  }
243  }
244  mp_set_rgb_from_yuv(mp, x, y, &p);
245  ++x;
246  }
247  }
248 }
249 
251 {
252  YuvPixel p;
253  int y, y0;
254 
255  av_assert1(mp->changes_map[0]);
256 
257  for (y = 0; y < mp->avctx->height; ++y) {
258  if (mp->changes_map[y * mp->avctx->width] != 0) {
259  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
260  p = mp_get_yuv_from_rgb(mp, 0, y);
261  } else {
262  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
263  p.y = av_clip_uintp2(p.y, 5);
264  if ((y & 3) == 0) {
265  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
266  p.v = av_clip_intp2(p.v, 5);
267  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
268  p.u = av_clip_intp2(p.u, 5);
269  }
270  mp->vpt[y] = p;
271  mp_set_rgb_from_yuv(mp, 0, y, &p);
272  }
273  }
274  for (y0 = 0; y0 < 2; ++y0)
275  for (y = y0; y < mp->avctx->height; y += 2)
276  mp_decode_line(mp, gb, y);
277 }
278 
279 static int mp_decode_frame(AVCodecContext *avctx,
280  void *data, int *got_frame,
281  AVPacket *avpkt)
282 {
283  const uint8_t *buf = avpkt->data;
284  int buf_size = avpkt->size;
285  MotionPixelsContext *mp = avctx->priv_data;
286  GetBitContext gb;
287  int i, count1, count2, sz, ret;
288 
289  if ((ret = ff_reget_buffer(avctx, mp->frame, 0)) < 0)
290  return ret;
291 
292  /* le32 bitstream msb first */
293  av_fast_padded_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size);
294  if (!mp->bswapbuf)
295  return AVERROR(ENOMEM);
296  mp->bdsp.bswap_buf((uint32_t *) mp->bswapbuf, (const uint32_t *) buf,
297  buf_size / 4);
298  if (buf_size & 3)
299  memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
300  init_get_bits(&gb, mp->bswapbuf, buf_size * 8);
301 
302  memset(mp->changes_map, 0, avctx->width * avctx->height);
303  for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
304  count1 = get_bits(&gb, 12);
305  count2 = get_bits(&gb, 12);
306  mp_read_changes_map(mp, &gb, count1, 8, i);
307  mp_read_changes_map(mp, &gb, count2, 4, i);
308  }
309 
310  mp->codes_count = get_bits(&gb, 4);
311  if (mp->codes_count == 0)
312  goto end;
313 
314  if (mp->changes_map[0] == 0) {
315  *(uint16_t *)mp->frame->data[0] = get_bits(&gb, 15);
316  mp->changes_map[0] = 1;
317  }
318  if (mp_read_codes_table(mp, &gb) < 0)
319  goto end;
320 
321  sz = get_bits(&gb, 18);
322  if (avctx->extradata[0] != 5)
323  sz += get_bits(&gb, 18);
324  if (sz == 0)
325  goto end;
326 
327  if (mp->max_codes_bits <= 0)
328  goto end;
329  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))
330  goto end;
331  mp_decode_frame_helper(mp, &gb);
332  ff_free_vlc(&mp->vlc);
333 
334 end:
335  if ((ret = av_frame_ref(data, mp->frame)) < 0)
336  return ret;
337  *got_frame = 1;
338  return buf_size;
339 }
340 
342  .name = "motionpixels",
343  .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
344  .type = AVMEDIA_TYPE_VIDEO,
346  .priv_data_size = sizeof(MotionPixelsContext),
347  .init = mp_decode_init,
348  .close = mp_decode_end,
350  .capabilities = AV_CODEC_CAP_DR1,
351  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
352 };
#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:308
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
uint8_t size
Definition: motionpixels.c:33
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:341
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:168
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:736
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
uint8_t delta
Definition: motionpixels.c:34
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:456
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:627
static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
Definition: motionpixels.c:177
uint8_t * data
Definition: packet.h:363
bitstream reader API header.
ptrdiff_t size
Definition: opengl_enc.c:100
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
#define init_vlc(vlc, nb_bits, nb_codes,bits, bits_wrap, bits_size,codes, codes_wrap, codes_size,flags)
Definition: vlc.h:38
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:153
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:1978
const char * name
Name of the codec implementation.
Definition: codec.h:197
GLsizei count
Definition: opengl_enc.c:108
BswapDSPContext bdsp
Definition: motionpixels.c:40
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:699
uint8_t w
Definition: llviddspenc.c:38
AVCodecContext * avctx
Definition: motionpixels.c:38
static int mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
Definition: motionpixels.c:124
static int mp_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: motionpixels.c:279
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:41
static void mp_decode_frame_helper(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:250
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:339
main external API structure.
Definition: avcodec.h:526
HuffCode codes[MAX_HUFF_CODES]
Definition: motionpixels.c:45
int extradata_size
Definition: avcodec.h:628
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
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:193
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:48
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:322
static void mp_decode_line(MotionPixelsContext *mp, GetBitContext *gb, int y)
Definition: motionpixels.c:203
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:95
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:387
#define MAX_HUFF_CODES
Definition: motionpixels.c:27
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
void * priv_data
Definition: avcodec.h:553
static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
Definition: motionpixels.c:185
static av_cold int mp_decode_end(AVCodecContext *avctx)
Definition: motionpixels.c:53
VLC_TYPE(* table)[2]
code, bits
Definition: vlc.h:28
static int mp_read_codes_table(MotionPixelsContext *mp, GetBitContext *gb)
Definition: motionpixels.c:146
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:358
#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
void * av_mallocz_array(size_t nmemb, size_t size)
Definition: mem.c:190