mirror of https://github.com/mpv-player/mpv
427 lines
11 KiB
C
427 lines
11 KiB
C
/*
|
|
* divx4_vbr.c
|
|
*
|
|
* Copyright (C) Thomas Östreich - June 2001
|
|
*
|
|
* 2-pass code OpenDivX port:
|
|
* Copyright (C) 2001 Christoph Lampert <gruel@gmx.de>
|
|
*
|
|
* This file is part of transcode, a linux video stream processing tool
|
|
*
|
|
* transcode is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2, or (at your option)
|
|
* any later version.
|
|
*
|
|
* transcode is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with GNU Make; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
*/
|
|
|
|
|
|
/**********************************************************
|
|
* Two-pass-code from OpenDivX *
|
|
* *
|
|
* Large parts of this code were taken from VbrControl() *
|
|
* from the OpenDivX project, (C) divxnetworks, *
|
|
* this code is published under DivX Open license, which *
|
|
* can be found... somewhere... oh, whatever... *
|
|
**********************************************************/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <math.h>
|
|
#include <inttypes.h>
|
|
|
|
#include "divx4_vbr.h"
|
|
|
|
//#include "transcode.h"
|
|
|
|
#define FALSE 0
|
|
#define TRUE 1
|
|
|
|
/* Absolute maximum and minimum quantizers used in VBR modes */
|
|
static const int min_quantizer=1;
|
|
static const int max_quantizer=31;
|
|
|
|
/* Limits on frame-level deviation of quantizer ( higher values
|
|
correspond to frames with more changes and vice versa ) */
|
|
static const float min_quant_delta=-10.f;
|
|
static const float max_quant_delta=5.f;
|
|
/* Limits on stream-level deviation of quantizer ( used to make
|
|
overall bitrate of stream close to requested value ) */
|
|
static const float min_rc_quant_delta=.6f;
|
|
static const float max_rc_quant_delta=1.5f;
|
|
|
|
/* Crispness parameter controls threshold for decision whether
|
|
to skip the frame or to code it. */
|
|
//static const float max_crispness=100.f;
|
|
/* Maximum allowed number of skipped frames in a line. */
|
|
//static const int max_drops_line=0; // CHL We don't drop frames at the moment!
|
|
|
|
|
|
typedef struct entry_s
|
|
/* max 28 bytes/frame or 5 Mb for 2-hour movie */
|
|
{
|
|
int quant;
|
|
int text_bits;
|
|
int motion_bits;
|
|
int total_bits;
|
|
float mult;
|
|
short is_key_frame;
|
|
short drop;
|
|
} entry;
|
|
|
|
static int m_iCount;
|
|
static int m_iQuant;
|
|
static int m_iCrispness;
|
|
static short m_bDrop;
|
|
static float m_fQuant;
|
|
|
|
static int64_t m_lEncodedBits;
|
|
static int64_t m_lExpectedBits;
|
|
|
|
static FILE *m_pFile;
|
|
|
|
static entry vFrame;
|
|
static entry *m_vFrames;
|
|
static long lFrameStart;
|
|
|
|
static int iNumFrames;
|
|
static int dummy;
|
|
|
|
|
|
void VbrControl_init_1pass_vbr(int quality, int crispness)
|
|
{
|
|
m_fQuant=min_quantizer+((max_quantizer-min_quantizer)/6.)*(6-quality);
|
|
m_iCount=0;
|
|
m_bDrop=FALSE;
|
|
VbrControl_update_1pass_vbr();
|
|
}
|
|
|
|
int VbrControl_init_2pass_vbr_analysis(const char *filename, int quality)
|
|
{
|
|
m_pFile=fopen(filename, "wb");
|
|
if(m_pFile==0)
|
|
return -1;
|
|
m_iCount=0;
|
|
m_bDrop=FALSE;
|
|
fprintf(m_pFile, "##version 1\n");
|
|
fprintf(m_pFile, "quality %d\n", quality);
|
|
return 0;
|
|
}
|
|
|
|
int VbrControl_init_2pass_vbr_encoding(const char *filename, int bitrate, double framerate, int crispness, int quality)
|
|
{
|
|
int i;
|
|
|
|
int64_t text_bits=0;
|
|
int64_t total_bits=0;
|
|
int64_t complexity=0;
|
|
int64_t new_complexity=0;
|
|
int64_t motion_bits=0;
|
|
int64_t denominator=0;
|
|
float qual_multiplier=1.;
|
|
char head[20];
|
|
|
|
int64_t desired_bits;
|
|
int64_t non_text_bits;
|
|
|
|
float average_complexity;
|
|
|
|
m_pFile=fopen(filename, "rb");
|
|
if(m_pFile==0)
|
|
return -1;
|
|
m_bDrop=FALSE;
|
|
m_iCount=0;
|
|
|
|
fread(head, 10, 1, m_pFile);
|
|
if(!strncmp("##version ", head, 10))
|
|
{
|
|
int version;
|
|
int iOldQual;
|
|
float old_qual, new_qual;
|
|
fscanf(m_pFile, "%d\n", &version);
|
|
fscanf(m_pFile, "quality %d\n", &iOldQual);
|
|
switch(iOldQual)
|
|
{
|
|
case 5:
|
|
old_qual=1.f;
|
|
break;
|
|
case 4:
|
|
old_qual=1.1f;
|
|
break;
|
|
case 3:
|
|
old_qual=1.25f;
|
|
break;
|
|
case 2:
|
|
old_qual=1.4f;
|
|
break;
|
|
case 1:
|
|
old_qual=2.f;
|
|
break;
|
|
}
|
|
switch(quality)
|
|
{
|
|
case 5:
|
|
new_qual=1.f;
|
|
break;
|
|
case 4:
|
|
new_qual=1.1f;
|
|
break;
|
|
case 3:
|
|
new_qual=1.25f;
|
|
break;
|
|
case 2:
|
|
new_qual=1.4f;
|
|
break;
|
|
case 1:
|
|
new_qual=2.f;
|
|
break;
|
|
}
|
|
qual_multiplier=new_qual/old_qual;
|
|
}
|
|
else
|
|
fseek(m_pFile, 0, SEEK_SET);
|
|
|
|
lFrameStart=ftell(m_pFile); // save current position
|
|
|
|
/* removed C++ dependencies, now read file twice :-( */
|
|
|
|
|
|
while(!feof(m_pFile))
|
|
{ fscanf(m_pFile, "Frame %d: intra %d, quant %d, texture %d, motion %d, total %d\n",
|
|
&iNumFrames, &(vFrame.is_key_frame), &(vFrame.quant), &(vFrame.text_bits), &(vFrame.motion_bits), &(vFrame.total_bits));
|
|
|
|
vFrame.total_bits+=vFrame.text_bits*(qual_multiplier-1);
|
|
vFrame.text_bits*=qual_multiplier;
|
|
text_bits +=(int64_t)vFrame.text_bits;
|
|
motion_bits += (int64_t)vFrame.motion_bits;
|
|
total_bits +=(int64_t)vFrame.total_bits;
|
|
complexity +=(int64_t)vFrame.text_bits*vFrame.quant;
|
|
|
|
// printf("Frames %d, texture %d, motion %d, quant %d total %d ",
|
|
// iNumFrames, vFrame.text_bits, vFrame.motion_bits, vFrame.quant, vFrame.total_bits);
|
|
// printf("texture %d, total %d, complexity %lld \n",vFrame.text_bits,vFrame.total_bits, complexity);
|
|
}
|
|
iNumFrames++;
|
|
average_complexity=complexity/iNumFrames;
|
|
|
|
// if (verbose & TC_DEBUG) {
|
|
// fprintf(stderr, "(%s) frames %d, texture %lld, motion %lld, total %lld, complexity %lld\n", __FILE__, iNumFrames, text_bits, motion_bits, total_bits, complexity);
|
|
// }
|
|
|
|
m_vFrames = (entry*)malloc(iNumFrames*sizeof(entry));
|
|
if (!m_vFrames)
|
|
{ printf("out of memory");
|
|
return -2; //TC_EXPORT_ERROR;
|
|
}
|
|
|
|
fseek(m_pFile, lFrameStart, SEEK_SET); // start again
|
|
|
|
for (i=0;i<iNumFrames;i++)
|
|
{ fscanf(m_pFile, "Frame %d: intra %d, quant %d, texture %d, motion %d, total %d\n",
|
|
&dummy, &(m_vFrames[i].is_key_frame), &(m_vFrames[i].quant),
|
|
&(m_vFrames[i].text_bits), &(m_vFrames[i].motion_bits),
|
|
&(m_vFrames[i].total_bits));
|
|
|
|
m_vFrames[i].total_bits += m_vFrames[i].text_bits*(qual_multiplier-1);
|
|
m_vFrames[i].text_bits *= qual_multiplier;
|
|
}
|
|
|
|
if (m_pFile)
|
|
{ fclose(m_pFile);
|
|
m_pFile=NULL;
|
|
}
|
|
|
|
desired_bits=(int64_t)bitrate*(int64_t)iNumFrames/framerate;
|
|
non_text_bits=total_bits-text_bits;
|
|
|
|
if(desired_bits<=non_text_bits)
|
|
{
|
|
char s[200];
|
|
printf("Specified bitrate is too low for this clip.\n"
|
|
"Minimum possible bitrate for the clip is %.0f kbps. Overriding\n"
|
|
"user-specified value.\n",
|
|
(float)(non_text_bits*framerate/(int64_t)iNumFrames));
|
|
|
|
desired_bits=non_text_bits*3/2;
|
|
/*
|
|
m_fQuant=max_quantizer;
|
|
for(int i=0; i<iNumFrames; i++)
|
|
{
|
|
m_vFrames[i].drop=0;
|
|
m_vFrames[i].mult=1;
|
|
}
|
|
VbrControl_set_quant(m_fQuant);
|
|
return 0;
|
|
*/
|
|
}
|
|
|
|
desired_bits -= non_text_bits;
|
|
/**
|
|
BRIEF EXPLANATION OF WHAT'S GOING ON HERE.
|
|
We assume that
|
|
text_bits=complexity / quantizer
|
|
total_bits-text_bits = const(complexity)
|
|
where 'complexity' is a characteristic of the frame
|
|
and does not depend much on quantizer dynamics.
|
|
Using this equation, we calculate 'average' quantizer
|
|
to be used for encoding ( 1st order effect ).
|
|
Having constant quantizer for the entire stream is not
|
|
very convenient - reconstruction errors are
|
|
more noticeable in low-motion scenes. To compensate
|
|
this effect, we multiply quantizer for each frame by
|
|
(complexity/average_complexity)^k,
|
|
( k - parameter of adjustment ). k=0 means 'no compensation'
|
|
and k=1 is 'constant bitrate mode'. We choose something in
|
|
between, like 0.5 ( 2nd order effect ).
|
|
**/
|
|
|
|
average_complexity=complexity/iNumFrames;
|
|
|
|
for(i=0; i<iNumFrames; i++)
|
|
{
|
|
float mult;
|
|
if(m_vFrames[i].is_key_frame)
|
|
{
|
|
if((i+1<iNumFrames) && (m_vFrames[i+1].is_key_frame))
|
|
mult=1.25;
|
|
else
|
|
mult=.75;
|
|
}
|
|
else
|
|
{
|
|
mult=m_vFrames[i].text_bits*m_vFrames[i].quant;
|
|
mult=(float)sqrt(mult/average_complexity);
|
|
|
|
// if(i && m_vFrames[i-1].is_key_frame)
|
|
// mult *= 0.75;
|
|
if(mult<0.5)
|
|
mult=0.5;
|
|
if(mult>1.5)
|
|
mult=1.5;
|
|
}
|
|
|
|
m_vFrames[i].mult=mult;
|
|
m_vFrames[i].drop=FALSE;
|
|
new_complexity+=m_vFrames[i].text_bits*m_vFrames[i].quant;
|
|
|
|
denominator+=desired_bits*m_vFrames[i].mult/iNumFrames;
|
|
}
|
|
|
|
m_fQuant=((double)new_complexity)/(double)denominator;
|
|
|
|
if(m_fQuant<min_quantizer) m_fQuant=min_quantizer;
|
|
if(m_fQuant>max_quantizer) m_fQuant=max_quantizer;
|
|
m_pFile=fopen("analyse.log", "wb");
|
|
if(m_pFile)
|
|
{
|
|
fprintf(m_pFile, "Total frames: %d Avg quantizer: %f\n",
|
|
iNumFrames, m_fQuant);
|
|
fprintf(m_pFile, "Expecting %12lld bits\n", desired_bits+non_text_bits);
|
|
fflush(m_pFile);
|
|
}
|
|
VbrControl_set_quant(m_fQuant*m_vFrames[0].mult);
|
|
m_lEncodedBits=m_lExpectedBits=0;
|
|
return 0;
|
|
}
|
|
|
|
int VbrControl_get_intra()
|
|
{
|
|
return m_vFrames[m_iCount].is_key_frame;
|
|
}
|
|
|
|
short VbrControl_get_drop()
|
|
{
|
|
return m_bDrop;
|
|
}
|
|
|
|
int VbrControl_get_quant()
|
|
{
|
|
return m_iQuant;
|
|
}
|
|
|
|
void VbrControl_set_quant(float quant)
|
|
{
|
|
m_iQuant=quant;
|
|
if((rand() % 10)<((quant-m_iQuant) * 10))
|
|
m_iQuant++;
|
|
if(m_iQuant<min_quantizer) m_iQuant=min_quantizer;
|
|
if(m_iQuant>max_quantizer) m_iQuant=max_quantizer;
|
|
}
|
|
|
|
void VbrControl_update_1pass_vbr()
|
|
{
|
|
VbrControl_set_quant(m_fQuant);
|
|
m_iCount++;
|
|
}
|
|
|
|
void VbrControl_update_2pass_vbr_analysis(int is_key_frame, int motion_bits, int texture_bits, int total_bits, int quant)
|
|
{
|
|
if(!m_pFile)
|
|
return;
|
|
fprintf(m_pFile, "Frame %d: intra %d, quant %d, texture %d, motion %d, total %d\n",
|
|
m_iCount, is_key_frame, quant, texture_bits, motion_bits, total_bits);
|
|
m_iCount++;
|
|
}
|
|
|
|
void VbrControl_update_2pass_vbr_encoding(int motion_bits, int texture_bits, int total_bits)
|
|
{
|
|
double q;
|
|
double dq;
|
|
|
|
if(m_iCount>=iNumFrames)
|
|
return;
|
|
|
|
m_lExpectedBits+=(m_vFrames[m_iCount].total_bits-m_vFrames[m_iCount].text_bits)
|
|
+ m_vFrames[m_iCount].text_bits*m_vFrames[m_iCount].quant/m_fQuant;
|
|
m_lEncodedBits+=(int64_t)total_bits;
|
|
|
|
if(m_pFile)
|
|
fprintf(m_pFile, "Frame %d: PRESENT, complexity %d, quant multiplier %f, texture %d, total %d ",
|
|
m_iCount, m_vFrames[m_iCount].text_bits*m_vFrames[m_iCount].quant,
|
|
m_vFrames[m_iCount].mult, texture_bits, total_bits);
|
|
|
|
m_iCount++;
|
|
|
|
q = m_fQuant * m_vFrames[m_iCount].mult;
|
|
if(q<m_fQuant+min_quant_delta) q=m_fQuant+min_quant_delta;
|
|
if(q>m_fQuant+max_quant_delta) q=m_fQuant+max_quant_delta;
|
|
|
|
dq = (double)m_lEncodedBits/(double)m_lExpectedBits;
|
|
dq*=dq;
|
|
if(dq<min_rc_quant_delta)
|
|
dq=min_rc_quant_delta;
|
|
if(dq>max_rc_quant_delta)
|
|
dq=max_rc_quant_delta;
|
|
if(m_iCount<20) // no framerate corrections in first frames
|
|
dq=1;
|
|
if(m_pFile)
|
|
fprintf(m_pFile, "Progress: expected %12lld, achieved %12lld, dq %f",
|
|
m_lExpectedBits, m_lEncodedBits, dq);
|
|
q *= dq;
|
|
VbrControl_set_quant(q);
|
|
if(m_pFile)
|
|
fprintf(m_pFile, ", new quant %d\n", m_iQuant);
|
|
}
|
|
|
|
void VbrControl_close()
|
|
{
|
|
if(m_pFile)
|
|
{
|
|
fclose(m_pFile);
|
|
m_pFile=NULL;
|
|
}
|
|
free(m_vFrames);
|
|
}
|