FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
msvideo1enc.c
Go to the documentation of this file.
1 /*
2  * Microsoft Video-1 Encoder
3  * Copyright (c) 2009 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  * Microsoft Video-1 encoder
25  */
26 
27 #include "avcodec.h"
28 #include "internal.h"
29 #include "bytestream.h"
30 #include "libavutil/lfg.h"
31 #include "elbg.h"
32 #include "libavutil/imgutils.h"
33 /**
34  * Encoder context
35  */
36 typedef struct Msvideo1EncContext {
40 
41  int block[16*3];
42  int block2[16*3];
43  int codebook[8*3];
44  int codebook2[8*3];
45  int output[16*3];
46  int output2[16*3];
47  int avg[3];
48  int bestpos;
49  int keyint;
51 
52 enum MSV1Mode{
53  MODE_SKIP = 0,
57 };
58 
59 #define SKIP_PREFIX 0x8400
60 #define SKIPS_MAX 0x03FF
61 #define MKRGB555(in, off) (((in)[off] << 10) | ((in)[(off) + 1] << 5) | ((in)[(off) + 2]))
62 
63 static const int remap[16] = { 0, 1, 4, 5, 2, 3, 6, 7, 8, 9, 12, 13, 10, 11, 14, 15 };
64 
66  const AVFrame *pict, int *got_packet)
67 {
68  Msvideo1EncContext * const c = avctx->priv_data;
69  const AVFrame *p = pict;
70  uint16_t *src;
71  uint8_t *prevptr;
72  uint8_t *dst, *buf;
73  int keyframe = 0;
74  int no_skips = 1;
75  int i, j, k, x, y, ret;
76  int skips = 0;
77  int quality = 24;
78 
79  if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width*avctx->height*9 + AV_INPUT_BUFFER_MIN_SIZE, 0)) < 0)
80  return ret;
81  dst= buf= pkt->data;
82 
83  if(!c->prev)
84  c->prev = av_malloc(avctx->width * 3 * (avctx->height + 3));
85  prevptr = c->prev + avctx->width * 3 * (FFALIGN(avctx->height, 4) - 1);
86  src = (uint16_t*)(p->data[0] + p->linesize[0]*(FFALIGN(avctx->height, 4) - 1));
87  if(c->keyint >= avctx->keyint_min)
88  keyframe = 1;
89 
90 
91  for(y = 0; y < avctx->height; y += 4){
92  for(x = 0; x < avctx->width; x += 4){
93  int bestmode = MODE_SKIP;
94  int bestscore = INT_MAX;
95  int flags = 0;
96  int score;
97 
98  for(j = 0; j < 4; j++){
99  for(i = 0; i < 4; i++){
100  uint16_t val = src[x + i - j*p->linesize[0]/2];
101  for(k = 0; k < 3; k++){
102  c->block[(i + j*4)*3 + k] =
103  c->block2[remap[i + j*4]*3 + k] = (val >> (10-k*5)) & 0x1F;
104  }
105  }
106  }
107  if(!keyframe){
108  bestscore = 0;
109  for(j = 0; j < 4; j++){
110  for(i = 0; i < 4*3; i++){
111  int t = prevptr[x*3 + i - j*3*avctx->width] - c->block[i + j*4*3];
112  bestscore += t*t;
113  }
114  }
115  bestscore /= quality;
116  }
117  // try to find optimal value to fill whole 4x4 block
118  score = 0;
119  avpriv_init_elbg(c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd);
120  avpriv_do_elbg (c->block, 3, 16, c->avg, 1, 1, c->output, &c->rnd);
121  if(c->avg[0] == 1) // red component = 1 will be written as skip code
122  c->avg[0] = 0;
123  for(j = 0; j < 4; j++){
124  for(i = 0; i < 4; i++){
125  for(k = 0; k < 3; k++){
126  int t = c->avg[k] - c->block[(i+j*4)*3+k];
127  score += t*t;
128  }
129  }
130  }
131  score /= quality;
132  score += 2;
133  if(score < bestscore){
134  bestscore = score;
135  bestmode = MODE_FILL;
136  }
137  // search for optimal filling of 2-color block
138  score = 0;
139  avpriv_init_elbg(c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd);
140  avpriv_do_elbg (c->block, 3, 16, c->codebook, 2, 1, c->output, &c->rnd);
141  // last output value should be always 1, swap codebooks if needed
142  if(!c->output[15]){
143  for(i = 0; i < 3; i++)
144  FFSWAP(uint8_t, c->codebook[i], c->codebook[i+3]);
145  for(i = 0; i < 16; i++)
146  c->output[i] ^= 1;
147  }
148  for(j = 0; j < 4; j++){
149  for(i = 0; i < 4; i++){
150  for(k = 0; k < 3; k++){
151  int t = c->codebook[c->output[i+j*4]*3 + k] - c->block[i*3+k+j*4*3];
152  score += t*t;
153  }
154  }
155  }
156  score /= quality;
157  score += 6;
158  if(score < bestscore){
159  bestscore = score;
160  bestmode = MODE_2COL;
161  }
162  // search for optimal filling of 2-color 2x2 subblocks
163  score = 0;
164  for(i = 0; i < 4; i++){
165  avpriv_init_elbg(c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd);
166  avpriv_do_elbg (c->block2 + i*4*3, 3, 4, c->codebook2 + i*2*3, 2, 1, c->output2 + i*4, &c->rnd);
167  }
168  // last value should be always 1, swap codebooks if needed
169  if(!c->output2[15]){
170  for(i = 0; i < 3; i++)
171  FFSWAP(uint8_t, c->codebook2[i+18], c->codebook2[i+21]);
172  for(i = 12; i < 16; i++)
173  c->output2[i] ^= 1;
174  }
175  for(j = 0; j < 4; j++){
176  for(i = 0; i < 4; i++){
177  for(k = 0; k < 3; k++){
178  int t = c->codebook2[(c->output2[remap[i+j*4]] + (i&2) + (j&2)*2)*3+k] - c->block[i*3+k + j*4*3];
179  score += t*t;
180  }
181  }
182  }
183  score /= quality;
184  score += 18;
185  if(score < bestscore){
186  bestscore = score;
187  bestmode = MODE_8COL;
188  }
189 
190  if(bestmode == MODE_SKIP){
191  skips++;
192  no_skips = 0;
193  }
194  if((bestmode != MODE_SKIP && skips) || skips == SKIPS_MAX){
195  bytestream_put_le16(&dst, skips | SKIP_PREFIX);
196  skips = 0;
197  }
198 
199  switch(bestmode){
200  case MODE_FILL:
201  bytestream_put_le16(&dst, MKRGB555(c->avg,0) | 0x8000);
202  for(j = 0; j < 4; j++)
203  for(i = 0; i < 4; i++)
204  for(k = 0; k < 3; k++)
205  prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->avg[k];
206  break;
207  case MODE_2COL:
208  for(j = 0; j < 4; j++){
209  for(i = 0; i < 4; i++){
210  flags |= (c->output[i + j*4]^1) << (i + j*4);
211  for(k = 0; k < 3; k++)
212  prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->codebook[c->output[i + j*4]*3 + k];
213  }
214  }
215  bytestream_put_le16(&dst, flags);
216  bytestream_put_le16(&dst, MKRGB555(c->codebook, 0));
217  bytestream_put_le16(&dst, MKRGB555(c->codebook, 3));
218  break;
219  case MODE_8COL:
220  for(j = 0; j < 4; j++){
221  for(i = 0; i < 4; i++){
222  flags |= (c->output2[remap[i + j*4]]^1) << (i + j*4);
223  for(k = 0; k < 3; k++)
224  prevptr[x*3 + i*3 + k - j*3*avctx->width] = c->codebook2[(c->output2[remap[i+j*4]] + (i&2) + (j&2)*2)*3 + k];
225  }
226  }
227  bytestream_put_le16(&dst, flags);
228  bytestream_put_le16(&dst, MKRGB555(c->codebook2, 0) | 0x8000);
229  for(i = 3; i < 24; i += 3)
230  bytestream_put_le16(&dst, MKRGB555(c->codebook2, i));
231  break;
232  }
233  }
234  src -= p->linesize[0] << 1;
235  prevptr -= avctx->width * 3 * 4;
236  }
237  if(skips)
238  bytestream_put_le16(&dst, skips | SKIP_PREFIX);
239  //EOF
240  bytestream_put_byte(&dst, 0);
241  bytestream_put_byte(&dst, 0);
242 
243  if(no_skips)
244  keyframe = 1;
245  if(keyframe)
246  c->keyint = 0;
247  else
248  c->keyint++;
249  if (keyframe) pkt->flags |= AV_PKT_FLAG_KEY;
250  pkt->size = dst - buf;
251  *got_packet = 1;
252 
253  return 0;
254 }
255 
256 
257 /**
258  * init encoder
259  */
261 {
262  Msvideo1EncContext * const c = avctx->priv_data;
263 
264  c->avctx = avctx;
265  if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
266  return -1;
267  }
268  if((avctx->width&3) || (avctx->height&3)){
269  av_log(avctx, AV_LOG_ERROR, "width and height must be multiples of 4\n");
270  return -1;
271  }
272 
273  avctx->bits_per_coded_sample = 16;
274 
275  c->keyint = avctx->keyint_min;
276  av_lfg_init(&c->rnd, 1);
277 
278  return 0;
279 }
280 
281 
282 
283 /**
284  * Uninit encoder
285  */
287 {
288  Msvideo1EncContext * const c = avctx->priv_data;
289 
290  av_freep(&c->prev);
291 
292  return 0;
293 }
294 
296  .name = "msvideo1",
297  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Video-1"),
298  .type = AVMEDIA_TYPE_VIDEO,
299  .id = AV_CODEC_ID_MSVIDEO1,
300  .priv_data_size = sizeof(Msvideo1EncContext),
301  .init = encode_init,
302  .encode2 = encode_frame,
303  .close = encode_end,
305 };
static av_cold int encode_init(AVCodecContext *avctx)
init encoder
Definition: msvideo1enc.c:260
Definition: lfg.h:25
const char const char void * val
Definition: avisynth_c.h:634
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
misc image utilities
int output2[16 *3]
Definition: msvideo1enc.c:46
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1589
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3559
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
int avpriv_do_elbg(int *points, int dim, int numpoints, int *codebook, int numCB, int max_steps, int *closest_cb, AVLFG *rand_state)
Implementation of the Enhanced LBG Algorithm Based on the paper "Neural Networks 14:1219-1237" that c...
Definition: elbg.c:371
uint8_t * data
Definition: avcodec.h:1588
int output[16 *3]
Definition: msvideo1enc.c:45
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:3050
#define AV_INPUT_BUFFER_MIN_SIZE
minimum encoding buffer size Used to avoid some checks during header writing.
Definition: avcodec.h:738
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1620
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet)
Definition: msvideo1enc.c:65
#define SKIP_PREFIX
Definition: msvideo1enc.c:59
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
const char * name
Name of the codec implementation.
Definition: avcodec.h:3566
int codebook[8 *3]
Definition: msvideo1enc.c:43
int block2[16 *3]
Definition: msvideo1enc.c:42
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1594
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:251
int width
picture width / height.
Definition: avcodec.h:1844
#define src
Definition: vp9dsp.c:530
int avpriv_init_elbg(int *points, int dim, int numpoints, int *codebook, int numCB, int max_steps, int *closest_cb, AVLFG *rand_state)
Initialize the **codebook vector for the elbg algorithm.
Definition: elbg.c:337
Libavcodec external API header.
static const int remap[16]
Definition: msvideo1enc.c:63
static av_cold int encode_end(AVCodecContext *avctx)
Uninit encoder.
Definition: msvideo1enc.c:286
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
int codebook2[8 *3]
Definition: msvideo1enc.c:44
main external API structure.
Definition: avcodec.h:1657
void * buf
Definition: avisynth_c.h:553
MSV1Mode
Definition: msvideo1enc.c:52
AVCodec ff_msvideo1_encoder
Definition: msvideo1enc.c:295
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:30
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1690
#define SKIPS_MAX
Definition: msvideo1enc.c:60
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:262
static int flags
Definition: cpu.c:47
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
int block[16 *3]
Definition: msvideo1enc.c:41
common internal api header.
static double c[64]
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:331
void * priv_data
Definition: avcodec.h:1699
AVCodecContext * avctx
Definition: msvideo1enc.c:37
Encoder context.
Definition: msvideo1enc.c:36
#define MKRGB555(in, off)
Definition: msvideo1enc.c:61
#define av_freep(p)
#define FFSWAP(type, a, b)
Definition: common.h:99
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1565
int keyint_min
minimum GOP size
Definition: avcodec.h:2330