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ffmpeg / libavcodec / libxvidff.c @ 79cb09b2

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1
/*
2
 * Interface to xvidcore for mpeg4 encoding
3
 * Copyright (c) 2004 Adam Thayer <krevnik@comcast.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
 *
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 * 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.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21

    
22
/**
23
 * @file xvidmpeg4.c
24
 * Interface to xvidcore for MPEG-4 compliant encoding.
25
 * @author Adam Thayer (krevnik@comcast.net)
26
 */
27

    
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#include <xvid.h>
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#include <unistd.h>
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#include "avcodec.h"
31
#include "libxvid_internal.h"
32

    
33
/**
34
 * Buffer management macros.
35
 */
36
#define BUFFER_SIZE                 1024
37
#define BUFFER_REMAINING(x)         (BUFFER_SIZE - strlen(x))
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#define BUFFER_CAT(x)               (&((x)[strlen(x)]))
39

    
40
/* For PPC Use */
41
int has_altivec(void);
42

    
43
/**
44
 * Structure for the private Xvid context.
45
 * This stores all the private context for the codec.
46
 */
47
struct xvid_context {
48
    void *encoder_handle;          /** Handle for Xvid encoder */
49
    int xsize, ysize;              /** Frame size */
50
    int vop_flags;                 /** VOP flags for Xvid encoder */
51
    int vol_flags;                 /** VOL flags for Xvid encoder */
52
    int me_flags;                  /** Motion Estimation flags */
53
    int qscale;                    /** Do we use constant scale? */
54
    int quicktime_format;          /** Are we in a QT-based format? */
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    AVFrame encoded_picture;       /** Encoded frame information */
56
    char *twopassbuffer;           /** Character buffer for two-pass */
57
    char *old_twopassbuffer;       /** Old character buffer (two-pass) */
58
    char *twopassfile;             /** second pass temp file name */
59
    unsigned char *intra_matrix;   /** P-Frame Quant Matrix */
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    unsigned char *inter_matrix;   /** I-Frame Quant Matrix */
61
};
62

    
63
/**
64
 * Structure for the private first-pass plugin.
65
 */
66
struct xvid_ff_pass1 {
67
    int     version;                /** Xvid version */
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    struct xvid_context *context;        /** Pointer to private context */
69
};
70

    
71
/* Prototypes - See function implementation for details */
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int xvid_strip_vol_header(AVCodecContext *avctx, unsigned char *frame, unsigned int header_len, unsigned int frame_len);
73
int xvid_ff_2pass(void *ref, int opt, void *p1, void *p2);
74
void xvid_correct_framerate(AVCodecContext *avctx);
75

    
76
/**
77
 * Creates the private context for the encoder.
78
 * All buffers are allocated, settings are loaded from the user,
79
 * and the encoder context created.
80
 *
81
 * @param avctx AVCodecContext pointer to context
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 * @return Returns 0 on success, -1 on failure
83
 */
84
av_cold int ff_xvid_encode_init(AVCodecContext *avctx)  {
85
    int xerr, i;
86
    int xvid_flags = avctx->flags;
87
    struct xvid_context *x = avctx->priv_data;
88
    uint16_t *intra, *inter;
89
    int fd;
90

    
91
    xvid_plugin_single_t single;
92
    struct xvid_ff_pass1 rc2pass1;
93
    xvid_plugin_2pass2_t rc2pass2;
94
    xvid_gbl_init_t xvid_gbl_init;
95
    xvid_enc_create_t xvid_enc_create;
96
    xvid_enc_plugin_t plugins[7];
97

    
98
    /* Bring in VOP flags from ffmpeg command-line */
99
    x->vop_flags = XVID_VOP_HALFPEL; /* Bare minimum quality */
100
    if( xvid_flags & CODEC_FLAG_4MV )
101
        x->vop_flags |= XVID_VOP_INTER4V; /* Level 3 */
102
    if( avctx->trellis
103
        )
104
        x->vop_flags |= XVID_VOP_TRELLISQUANT; /* Level 5 */
105
    if( xvid_flags & CODEC_FLAG_AC_PRED )
106
        x->vop_flags |= XVID_VOP_HQACPRED; /* Level 6 */
107
    if( xvid_flags & CODEC_FLAG_GRAY )
108
        x->vop_flags |= XVID_VOP_GREYSCALE;
109

    
110
    /* Decide which ME quality setting to use */
111
    x->me_flags = 0;
112
    switch( avctx->me_method ) {
113
       case ME_FULL:   /* Quality 6 */
114
           x->me_flags |=  XVID_ME_EXTSEARCH16
115
                       |   XVID_ME_EXTSEARCH8;
116

    
117
       case ME_EPZS:   /* Quality 4 */
118
           x->me_flags |=  XVID_ME_ADVANCEDDIAMOND8
119
                       |   XVID_ME_HALFPELREFINE8
120
                       |   XVID_ME_CHROMA_PVOP
121
                       |   XVID_ME_CHROMA_BVOP;
122

    
123
       case ME_LOG:    /* Quality 2 */
124
       case ME_PHODS:
125
       case ME_X1:
126
           x->me_flags |=  XVID_ME_ADVANCEDDIAMOND16
127
                       |   XVID_ME_HALFPELREFINE16;
128

    
129
       case ME_ZERO:   /* Quality 0 */
130
       default:
131
           break;
132
    }
133

    
134
    /* Decide how we should decide blocks */
135
    switch( avctx->mb_decision ) {
136
       case 2:
137
           x->vop_flags |= XVID_VOP_MODEDECISION_RD;
138
           x->me_flags |=  XVID_ME_HALFPELREFINE8_RD
139
                       |   XVID_ME_QUARTERPELREFINE8_RD
140
                       |   XVID_ME_EXTSEARCH_RD
141
                       |   XVID_ME_CHECKPREDICTION_RD;
142
       case 1:
143
           if( !(x->vop_flags & XVID_VOP_MODEDECISION_RD) )
144
               x->vop_flags |= XVID_VOP_FAST_MODEDECISION_RD;
145
           x->me_flags |=  XVID_ME_HALFPELREFINE16_RD
146
                       |   XVID_ME_QUARTERPELREFINE16_RD;
147

    
148
       default:
149
           break;
150
    }
151

    
152
    /* Bring in VOL flags from ffmpeg command-line */
153
    x->vol_flags = 0;
154
    if( xvid_flags & CODEC_FLAG_GMC ) {
155
        x->vol_flags |= XVID_VOL_GMC;
156
        x->me_flags |= XVID_ME_GME_REFINE;
157
    }
158
    if( xvid_flags & CODEC_FLAG_QPEL ) {
159
        x->vol_flags |= XVID_VOL_QUARTERPEL;
160
        x->me_flags |= XVID_ME_QUARTERPELREFINE16;
161
        if( x->vop_flags & XVID_VOP_INTER4V )
162
            x->me_flags |= XVID_ME_QUARTERPELREFINE8;
163
    }
164

    
165
    memset(&xvid_gbl_init, 0, sizeof(xvid_gbl_init));
166
    xvid_gbl_init.version = XVID_VERSION;
167
    xvid_gbl_init.debug = 0;
168

    
169
#ifdef ARCH_PPC
170
    /* Xvid's PPC support is borked, use libavcodec to detect */
171
#ifdef HAVE_ALTIVEC
172
    if( has_altivec() ) {
173
        xvid_gbl_init.cpu_flags = XVID_CPU_FORCE | XVID_CPU_ALTIVEC;
174
    } else
175
#endif
176
        xvid_gbl_init.cpu_flags = XVID_CPU_FORCE;
177
#else
178
    /* Xvid can detect on x86 */
179
    xvid_gbl_init.cpu_flags = 0;
180
#endif
181

    
182
    /* Initialize */
183
    xvid_global(NULL, XVID_GBL_INIT, &xvid_gbl_init, NULL);
184

    
185
    /* Create the encoder reference */
186
    memset(&xvid_enc_create, 0, sizeof(xvid_enc_create));
187
    xvid_enc_create.version = XVID_VERSION;
188

    
189
    /* Store the desired frame size */
190
    xvid_enc_create.width = x->xsize = avctx->width;
191
    xvid_enc_create.height = x->ysize = avctx->height;
192

    
193
    /* Xvid can determine the proper profile to use */
194
    /* xvid_enc_create.profile = XVID_PROFILE_S_L3; */
195

    
196
    /* We don't use zones */
197
    xvid_enc_create.zones = NULL;
198
    xvid_enc_create.num_zones = 0;
199

    
200
    xvid_enc_create.num_threads = avctx->thread_count;
201

    
202
    xvid_enc_create.plugins = plugins;
203
    xvid_enc_create.num_plugins = 0;
204

    
205
    /* Initialize Buffers */
206
    x->twopassbuffer = NULL;
207
    x->old_twopassbuffer = NULL;
208
    x->twopassfile = NULL;
209

    
210
    if( xvid_flags & CODEC_FLAG_PASS1 ) {
211
        memset(&rc2pass1, 0, sizeof(struct xvid_ff_pass1));
212
        rc2pass1.version = XVID_VERSION;
213
        rc2pass1.context = x;
214
        x->twopassbuffer = av_malloc(BUFFER_SIZE);
215
        x->old_twopassbuffer = av_malloc(BUFFER_SIZE);
216
        if( x->twopassbuffer == NULL || x->old_twopassbuffer == NULL ) {
217
            av_log(avctx, AV_LOG_ERROR,
218
                "Xvid: Cannot allocate 2-pass log buffers\n");
219
            return -1;
220
        }
221
        x->twopassbuffer[0] = x->old_twopassbuffer[0] = 0;
222

    
223
        plugins[xvid_enc_create.num_plugins].func = xvid_ff_2pass;
224
        plugins[xvid_enc_create.num_plugins].param = &rc2pass1;
225
        xvid_enc_create.num_plugins++;
226
    } else if( xvid_flags & CODEC_FLAG_PASS2 ) {
227
        memset(&rc2pass2, 0, sizeof(xvid_plugin_2pass2_t));
228
        rc2pass2.version = XVID_VERSION;
229
        rc2pass2.bitrate = avctx->bit_rate;
230

    
231
        fd = av_tempfile("xvidff.", &(x->twopassfile));
232
        if( fd == -1 ) {
233
            av_log(avctx, AV_LOG_ERROR,
234
                "Xvid: Cannot write 2-pass pipe\n");
235
            return -1;
236
        }
237

    
238
        if( avctx->stats_in == NULL ) {
239
            av_log(avctx, AV_LOG_ERROR,
240
                "Xvid: No 2-pass information loaded for second pass\n");
241
            return -1;
242
        }
243

    
244
        if( strlen(avctx->stats_in) >
245
              write(fd, avctx->stats_in, strlen(avctx->stats_in)) ) {
246
            close(fd);
247
            av_log(avctx, AV_LOG_ERROR,
248
                "Xvid: Cannot write to 2-pass pipe\n");
249
            return -1;
250
        }
251

    
252
        close(fd);
253
        rc2pass2.filename = x->twopassfile;
254
        plugins[xvid_enc_create.num_plugins].func = xvid_plugin_2pass2;
255
        plugins[xvid_enc_create.num_plugins].param = &rc2pass2;
256
        xvid_enc_create.num_plugins++;
257
    } else if( !(xvid_flags & CODEC_FLAG_QSCALE) ) {
258
        /* Single Pass Bitrate Control! */
259
        memset(&single, 0, sizeof(xvid_plugin_single_t));
260
        single.version = XVID_VERSION;
261
        single.bitrate = avctx->bit_rate;
262

    
263
        plugins[xvid_enc_create.num_plugins].func = xvid_plugin_single;
264
        plugins[xvid_enc_create.num_plugins].param = &single;
265
        xvid_enc_create.num_plugins++;
266
    }
267

    
268
    /* Luminance Masking */
269
    if( 0.0 != avctx->lumi_masking ) {
270
        plugins[xvid_enc_create.num_plugins].func = xvid_plugin_lumimasking;
271
        plugins[xvid_enc_create.num_plugins].param = NULL;
272
        xvid_enc_create.num_plugins++;
273
    }
274

    
275
    /* Frame Rate and Key Frames */
276
    xvid_correct_framerate(avctx);
277
    xvid_enc_create.fincr = avctx->time_base.num;
278
    xvid_enc_create.fbase = avctx->time_base.den;
279
    if( avctx->gop_size > 0 )
280
        xvid_enc_create.max_key_interval = avctx->gop_size;
281
    else
282
        xvid_enc_create.max_key_interval = 240; /* Xvid's best default */
283

    
284
    /* Quants */
285
    if( xvid_flags & CODEC_FLAG_QSCALE ) x->qscale = 1;
286
    else x->qscale = 0;
287

    
288
    xvid_enc_create.min_quant[0] = avctx->qmin;
289
    xvid_enc_create.min_quant[1] = avctx->qmin;
290
    xvid_enc_create.min_quant[2] = avctx->qmin;
291
    xvid_enc_create.max_quant[0] = avctx->qmax;
292
    xvid_enc_create.max_quant[1] = avctx->qmax;
293
    xvid_enc_create.max_quant[2] = avctx->qmax;
294

    
295
    /* Quant Matrices */
296
    x->intra_matrix = x->inter_matrix = NULL;
297
    if( avctx->mpeg_quant )
298
       x->vol_flags |= XVID_VOL_MPEGQUANT;
299
    if( (avctx->intra_matrix || avctx->inter_matrix) ) {
300
       x->vol_flags |= XVID_VOL_MPEGQUANT;
301

    
302
       if( avctx->intra_matrix ) {
303
           intra = avctx->intra_matrix;
304
           x->intra_matrix = av_malloc(sizeof(unsigned char) * 64);
305
       } else
306
           intra = NULL;
307
       if( avctx->inter_matrix ) {
308
           inter = avctx->inter_matrix;
309
           x->inter_matrix = av_malloc(sizeof(unsigned char) * 64);
310
       } else
311
           inter = NULL;
312

    
313
       for( i = 0; i < 64; i++ ) {
314
           if( intra )
315
               x->intra_matrix[i] = (unsigned char)intra[i];
316
           if( inter )
317
               x->inter_matrix[i] = (unsigned char)inter[i];
318
       }
319
    }
320

    
321
    /* Misc Settings */
322
    xvid_enc_create.frame_drop_ratio = 0;
323
    xvid_enc_create.global = 0;
324
    if( xvid_flags & CODEC_FLAG_CLOSED_GOP )
325
        xvid_enc_create.global |= XVID_GLOBAL_CLOSED_GOP;
326

    
327
    /* Determines which codec mode we are operating in */
328
    avctx->extradata = NULL;
329
    avctx->extradata_size = 0;
330
    if( xvid_flags & CODEC_FLAG_GLOBAL_HEADER ) {
331
        /* In this case, we are claiming to be MPEG4 */
332
        x->quicktime_format = 1;
333
        avctx->codec_id = CODEC_ID_MPEG4;
334
    } else {
335
        /* We are claiming to be Xvid */
336
        x->quicktime_format = 0;
337
        if(!avctx->codec_tag)
338
            avctx->codec_tag = ff_get_fourcc("xvid");
339
    }
340

    
341
    /* Bframes */
342
    xvid_enc_create.max_bframes = avctx->max_b_frames;
343
    xvid_enc_create.bquant_offset = 100 * avctx->b_quant_offset;
344
    xvid_enc_create.bquant_ratio = 100 * avctx->b_quant_factor;
345
    if( avctx->max_b_frames > 0  && !x->quicktime_format ) xvid_enc_create.global |= XVID_GLOBAL_PACKED;
346

    
347
    /* Create encoder context */
348
    xerr = xvid_encore(NULL, XVID_ENC_CREATE, &xvid_enc_create, NULL);
349
    if( xerr ) {
350
        av_log(avctx, AV_LOG_ERROR, "Xvid: Could not create encoder reference\n");
351
        return -1;
352
    }
353

    
354
    x->encoder_handle = xvid_enc_create.handle;
355
    avctx->coded_frame = &x->encoded_picture;
356

    
357
    return 0;
358
}
359

    
360
/**
361
 * Encodes a single frame.
362
 *
363
 * @param avctx AVCodecContext pointer to context
364
 * @param frame Pointer to encoded frame buffer
365
 * @param buf_size Size of encoded frame buffer
366
 * @param data Pointer to AVFrame of unencoded frame
367
 * @return Returns 0 on success, -1 on failure
368
 */
369
int ff_xvid_encode_frame(AVCodecContext *avctx,
370
                         unsigned char *frame, int buf_size, void *data) {
371
    int xerr, i;
372
    char *tmp;
373
    struct xvid_context *x = avctx->priv_data;
374
    AVFrame *picture = data;
375
    AVFrame *p = &(x->encoded_picture);
376

    
377
    xvid_enc_frame_t xvid_enc_frame;
378
    xvid_enc_stats_t xvid_enc_stats;
379

    
380
    /* Start setting up the frame */
381
    memset(&xvid_enc_frame, 0, sizeof(xvid_enc_frame));
382
    xvid_enc_frame.version = XVID_VERSION;
383
    memset(&xvid_enc_stats, 0, sizeof(xvid_enc_stats));
384
    xvid_enc_stats.version = XVID_VERSION;
385
    *p = *picture;
386

    
387
    /* Let Xvid know where to put the frame. */
388
    xvid_enc_frame.bitstream = frame;
389
    xvid_enc_frame.length = buf_size;
390

    
391
    /* Initialize input image fields */
392
    if( avctx->pix_fmt != PIX_FMT_YUV420P ) {
393
        av_log(avctx, AV_LOG_ERROR, "Xvid: Color spaces other than 420p not supported\n");
394
        return -1;
395
    }
396

    
397
    xvid_enc_frame.input.csp = XVID_CSP_PLANAR; /* YUV420P */
398

    
399
    for( i = 0; i < 4; i++ ) {
400
        xvid_enc_frame.input.plane[i] = picture->data[i];
401
        xvid_enc_frame.input.stride[i] = picture->linesize[i];
402
    }
403

    
404
    /* Encoder Flags */
405
    xvid_enc_frame.vop_flags = x->vop_flags;
406
    xvid_enc_frame.vol_flags = x->vol_flags;
407
    xvid_enc_frame.motion = x->me_flags;
408
    xvid_enc_frame.type = XVID_TYPE_AUTO;
409

    
410
    /* Pixel aspect ratio setting */
411
    if (avctx->sample_aspect_ratio.num < 1 || avctx->sample_aspect_ratio.num > 255 ||
412
        avctx->sample_aspect_ratio.den < 1 || avctx->sample_aspect_ratio.den > 255) {
413
        av_log(avctx, AV_LOG_ERROR, "Invalid pixel aspect ratio %i/%i\n",
414
               avctx->sample_aspect_ratio.num, avctx->sample_aspect_ratio.den);
415
        return -1;
416
    }
417
    xvid_enc_frame.par = XVID_PAR_EXT;
418
    xvid_enc_frame.par_width  = avctx->sample_aspect_ratio.num;
419
    xvid_enc_frame.par_height = avctx->sample_aspect_ratio.den;
420

    
421
    /* Quant Setting */
422
    if( x->qscale ) xvid_enc_frame.quant = picture->quality / FF_QP2LAMBDA;
423
    else xvid_enc_frame.quant = 0;
424

    
425
    /* Matrices */
426
    xvid_enc_frame.quant_intra_matrix = x->intra_matrix;
427
    xvid_enc_frame.quant_inter_matrix = x->inter_matrix;
428

    
429
    /* Encode */
430
    xerr = xvid_encore(x->encoder_handle, XVID_ENC_ENCODE,
431
        &xvid_enc_frame, &xvid_enc_stats);
432

    
433
    /* Two-pass log buffer swapping */
434
    avctx->stats_out = NULL;
435
    if( x->twopassbuffer ) {
436
        tmp = x->old_twopassbuffer;
437
        x->old_twopassbuffer = x->twopassbuffer;
438
        x->twopassbuffer = tmp;
439
        x->twopassbuffer[0] = 0;
440
        if( x->old_twopassbuffer[0] != 0 ) {
441
            avctx->stats_out = x->old_twopassbuffer;
442
        }
443
    }
444

    
445
    if( 0 <= xerr ) {
446
        p->quality = xvid_enc_stats.quant * FF_QP2LAMBDA;
447
        if( xvid_enc_stats.type == XVID_TYPE_PVOP )
448
            p->pict_type = FF_P_TYPE;
449
        else if( xvid_enc_stats.type == XVID_TYPE_BVOP )
450
            p->pict_type = FF_B_TYPE;
451
        else if( xvid_enc_stats.type == XVID_TYPE_SVOP )
452
            p->pict_type = FF_S_TYPE;
453
        else
454
            p->pict_type = FF_I_TYPE;
455
        if( xvid_enc_frame.out_flags & XVID_KEYFRAME ) {
456
            p->key_frame = 1;
457
            if( x->quicktime_format )
458
                return xvid_strip_vol_header(avctx, frame,
459
                    xvid_enc_stats.hlength, xerr);
460
         } else
461
            p->key_frame = 0;
462

    
463
        return xerr;
464
    } else {
465
        av_log(avctx, AV_LOG_ERROR, "Xvid: Encoding Error Occurred: %i\n", xerr);
466
        return -1;
467
    }
468
}
469

    
470
/**
471
 * Destroys the private context for the encoder.
472
 * All buffers are freed, and the Xvid encoder context is destroyed.
473
 *
474
 * @param avctx AVCodecContext pointer to context
475
 * @return Returns 0, success guaranteed
476
 */
477
av_cold int ff_xvid_encode_close(AVCodecContext *avctx) {
478
    struct xvid_context *x = avctx->priv_data;
479

    
480
    xvid_encore(x->encoder_handle, XVID_ENC_DESTROY, NULL, NULL);
481

    
482
    if( avctx->extradata != NULL )
483
        av_free(avctx->extradata);
484
    if( x->twopassbuffer != NULL ) {
485
        av_free(x->twopassbuffer);
486
        av_free(x->old_twopassbuffer);
487
    }
488
    if( x->twopassfile != NULL )
489
        av_free(x->twopassfile);
490
    if( x->intra_matrix != NULL )
491
        av_free(x->intra_matrix);
492
    if( x->inter_matrix != NULL )
493
        av_free(x->inter_matrix);
494

    
495
    return 0;
496
}
497

    
498
/**
499
 * Routine to create a global VO/VOL header for MP4 container.
500
 * What we do here is extract the header from the Xvid bitstream
501
 * as it is encoded. We also strip the repeated headers from the
502
 * bitstream when a global header is requested for MPEG-4 ISO
503
 * compliance.
504
 *
505
 * @param avctx AVCodecContext pointer to context
506
 * @param frame Pointer to encoded frame data
507
 * @param header_len Length of header to search
508
 * @param frame_len Length of encoded frame data
509
 * @return Returns new length of frame data
510
 */
511
int xvid_strip_vol_header(AVCodecContext *avctx,
512
                  unsigned char *frame,
513
                  unsigned int header_len,
514
                  unsigned int frame_len) {
515
    int vo_len = 0, i;
516

    
517
    for( i = 0; i < header_len - 3; i++ ) {
518
        if( frame[i] == 0x00 &&
519
            frame[i+1] == 0x00 &&
520
            frame[i+2] == 0x01 &&
521
            frame[i+3] == 0xB6 ) {
522
            vo_len = i;
523
            break;
524
        }
525
    }
526

    
527
    if( vo_len > 0 ) {
528
        /* We need to store the header, so extract it */
529
        if( avctx->extradata == NULL ) {
530
            avctx->extradata = av_malloc(vo_len);
531
            memcpy(avctx->extradata, frame, vo_len);
532
            avctx->extradata_size = vo_len;
533
        }
534
        /* Less dangerous now, memmove properly copies the two
535
           chunks of overlapping data */
536
        memmove(frame, &(frame[vo_len]), frame_len - vo_len);
537
        return frame_len - vo_len;
538
    } else
539
        return frame_len;
540
}
541

    
542
/**
543
 * Routine to correct a possibly erroneous framerate being fed to us.
544
 * Xvid currently chokes on framerates where the ticks per frame is
545
 * extremely large. This function works to correct problems in this area
546
 * by estimating a new framerate and taking the simpler fraction of
547
 * the two presented.
548
 *
549
 * @param avctx Context that contains the framerate to correct.
550
 */
551
void xvid_correct_framerate(AVCodecContext *avctx) {
552
    int frate, fbase;
553
    int est_frate, est_fbase;
554
    int gcd;
555
    float est_fps, fps;
556

    
557
    frate = avctx->time_base.den;
558
    fbase = avctx->time_base.num;
559

    
560
    gcd = ff_gcd(frate, fbase);
561
    if( gcd > 1 ) {
562
        frate /= gcd;
563
        fbase /= gcd;
564
    }
565

    
566
    if( frate <= 65000 && fbase <= 65000 ) {
567
        avctx->time_base.den = frate;
568
        avctx->time_base.num = fbase;
569
        return;
570
    }
571

    
572
    fps = (float)frate / (float)fbase;
573
    est_fps = roundf(fps * 1000.0) / 1000.0;
574

    
575
    est_frate = (int)est_fps;
576
    if( est_fps > (int)est_fps ) {
577
        est_frate = (est_frate + 1) * 1000;
578
        est_fbase = (int)roundf((float)est_frate / est_fps);
579
    } else
580
        est_fbase = 1;
581

    
582
    gcd = ff_gcd(est_frate, est_fbase);
583
    if( gcd > 1 ) {
584
        est_frate /= gcd;
585
        est_fbase /= gcd;
586
    }
587

    
588
    if( fbase > est_fbase ) {
589
        avctx->time_base.den = est_frate;
590
        avctx->time_base.num = est_fbase;
591
        av_log(avctx, AV_LOG_DEBUG,
592
            "Xvid: framerate re-estimated: %.2f, %.3f%% correction\n",
593
            est_fps, (((est_fps - fps)/fps) * 100.0));
594
    } else {
595
        avctx->time_base.den = frate;
596
        avctx->time_base.num = fbase;
597
    }
598
}
599

    
600
/*
601
 * Xvid 2-Pass Kludge Section
602
 *
603
 * Xvid's default 2-pass doesn't allow us to create data as we need to, so
604
 * this section spends time replacing the first pass plugin so we can write
605
 * statistic information as libavcodec requests in. We have another kludge
606
 * that allows us to pass data to the second pass in Xvid without a custom
607
 * rate-control plugin.
608
 */
609

    
610
/**
611
 * Initializes the two-pass plugin and context.
612
 *
613
 * @param param Input construction parameter structure
614
 * @param handle Private context handle
615
 * @return Returns XVID_ERR_xxxx on failure, or 0 on success.
616
 */
617
static int xvid_ff_2pass_create(xvid_plg_create_t * param,
618
                                void ** handle) {
619
    struct xvid_ff_pass1 *x = (struct xvid_ff_pass1 *)param->param;
620
    char *log = x->context->twopassbuffer;
621

    
622
    /* Do a quick bounds check */
623
    if( log == NULL )
624
        return XVID_ERR_FAIL;
625

    
626
    /* We use snprintf() */
627
    /* This is because we can safely prevent a buffer overflow */
628
    log[0] = 0;
629
    snprintf(log, BUFFER_REMAINING(log),
630
        "# ffmpeg 2-pass log file, using xvid codec\n");
631
    snprintf(BUFFER_CAT(log), BUFFER_REMAINING(log),
632
        "# Do not modify. libxvidcore version: %d.%d.%d\n\n",
633
        XVID_VERSION_MAJOR(XVID_VERSION),
634
        XVID_VERSION_MINOR(XVID_VERSION),
635
        XVID_VERSION_PATCH(XVID_VERSION));
636

    
637
    *handle = x->context;
638
    return 0;
639
}
640

    
641
/**
642
 * Destroys the two-pass plugin context.
643
 *
644
 * @param ref Context pointer for the plugin
645
 * @param param Destrooy context
646
 * @return Returns 0, success guaranteed
647
 */
648
static int xvid_ff_2pass_destroy(struct xvid_context *ref,
649
                                xvid_plg_destroy_t *param) {
650
    /* Currently cannot think of anything to do on destruction */
651
    /* Still, the framework should be here for reference/use */
652
    if( ref->twopassbuffer != NULL )
653
        ref->twopassbuffer[0] = 0;
654
    return 0;
655
}
656

    
657
/**
658
 * Enables fast encode mode during the first pass.
659
 *
660
 * @param ref Context pointer for the plugin
661
 * @param param Frame data
662
 * @return Returns 0, success guaranteed
663
 */
664
static int xvid_ff_2pass_before(struct xvid_context *ref,
665
                                xvid_plg_data_t *param) {
666
    int motion_remove;
667
    int motion_replacements;
668
    int vop_remove;
669

    
670
    /* Nothing to do here, result is changed too much */
671
    if( param->zone && param->zone->mode == XVID_ZONE_QUANT )
672
        return 0;
673

    
674
    /* We can implement a 'turbo' first pass mode here */
675
    param->quant = 2;
676

    
677
    /* Init values */
678
    motion_remove = ~XVID_ME_CHROMA_PVOP &
679
                    ~XVID_ME_CHROMA_BVOP &
680
                    ~XVID_ME_EXTSEARCH16 &
681
                    ~XVID_ME_ADVANCEDDIAMOND16;
682
    motion_replacements = XVID_ME_FAST_MODEINTERPOLATE |
683
                          XVID_ME_SKIP_DELTASEARCH |
684
                          XVID_ME_FASTREFINE16 |
685
                          XVID_ME_BFRAME_EARLYSTOP;
686
    vop_remove = ~XVID_VOP_MODEDECISION_RD &
687
                 ~XVID_VOP_FAST_MODEDECISION_RD &
688
                 ~XVID_VOP_TRELLISQUANT &
689
                 ~XVID_VOP_INTER4V &
690
                 ~XVID_VOP_HQACPRED;
691

    
692
    param->vol_flags &= ~XVID_VOL_GMC;
693
    param->vop_flags &= vop_remove;
694
    param->motion_flags &= motion_remove;
695
    param->motion_flags |= motion_replacements;
696

    
697
    return 0;
698
}
699

    
700
/**
701
 * Captures statistic data and writes it during first pass.
702
 *
703
 * @param ref Context pointer for the plugin
704
 * @param param Statistic data
705
 * @return Returns XVID_ERR_xxxx on failure, or 0 on success
706
 */
707
static int xvid_ff_2pass_after(struct xvid_context *ref,
708
                                xvid_plg_data_t *param) {
709
    char *log = ref->twopassbuffer;
710
    char *frame_types = " ipbs";
711
    char frame_type;
712

    
713
    /* Quick bounds check */
714
    if( log == NULL )
715
        return XVID_ERR_FAIL;
716

    
717
    /* Convert the type given to us into a character */
718
    if( param->type < 5 && param->type > 0 ) {
719
        frame_type = frame_types[param->type];
720
    } else {
721
        return XVID_ERR_FAIL;
722
    }
723

    
724
    snprintf(BUFFER_CAT(log), BUFFER_REMAINING(log),
725
        "%c %d %d %d %d %d %d\n",
726
        frame_type, param->stats.quant, param->stats.kblks, param->stats.mblks,
727
        param->stats.ublks, param->stats.length, param->stats.hlength);
728

    
729
    return 0;
730
}
731

    
732
/**
733
 * Dispatch function for our custom plugin.
734
 * This handles the dispatch for the Xvid plugin. It passes data
735
 * on to other functions for actual processing.
736
 *
737
 * @param ref Context pointer for the plugin
738
 * @param cmd The task given for us to complete
739
 * @param p1 First parameter (varies)
740
 * @param p2 Second parameter (varies)
741
 * @return Returns XVID_ERR_xxxx on failure, or 0 on success
742
 */
743
int xvid_ff_2pass(void *ref, int cmd, void *p1, void *p2) {
744
    switch( cmd ) {
745
        case XVID_PLG_INFO:
746
        case XVID_PLG_FRAME:
747
            return 0;
748

    
749
        case XVID_PLG_BEFORE:
750
            return xvid_ff_2pass_before(ref, p1);
751

    
752
        case XVID_PLG_CREATE:
753
            return xvid_ff_2pass_create(p1, p2);
754

    
755
        case XVID_PLG_AFTER:
756
            return xvid_ff_2pass_after(ref, p1);
757

    
758
        case XVID_PLG_DESTROY:
759
            return xvid_ff_2pass_destroy(ref, p1);
760

    
761
        default:
762
            return XVID_ERR_FAIL;
763
    }
764
}
765

    
766
/**
767
 * Xvid codec definition for libavcodec.
768
 */
769
AVCodec libxvid_encoder = {
770
    "libxvid",
771
    CODEC_TYPE_VIDEO,
772
    CODEC_ID_XVID,
773
    sizeof(struct xvid_context),
774
    ff_xvid_encode_init,
775
    ff_xvid_encode_frame,
776
    ff_xvid_encode_close,
777
    .pix_fmts= (enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_NONE},
778
    .long_name= NULL_IF_CONFIG_SMALL("libxvidcore MPEG-4 part 2"),
779
};