You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
tdemultimedia/xine_artsplugin/tools/thumbnail/videoscaler.cpp

259 lines
7.0 KiB

/*
This file is part of KDE/aRts - xine integration
Copyright (C) 2003 Ewald Snel <ewald@rambo.its.tudelft.nl>
This program 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 of the License, or
(at your option) any later version.
inspired by code from the xine project
Copyright (C) 2003 the xine project
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <config.h>
#ifdef HAVE_ALLOCA_H
#include <alloca.h>
#endif
#include "videoscaler.h"
#define THUMBNAIL_BRIGHTNESS +32
#define THUMBNAIL_CONTRAST 128
#define THUMBNAIL_SATURATION 128
// Colorspace conversion tables
static int tableLY[256];
static int tableRV[256], tableBU[256], tableGU[256], tableGV[256];
static int clipR[2240], clipG[2240], clipB[2240];
static pthread_once_t once_control = PTHREAD_ONCE_INIT;
static void init_once_routine()
{
int cly = ( 76309 * THUMBNAIL_CONTRAST + 64) / 128;
int crv = (104597 * THUMBNAIL_SATURATION + 64) / 128;
int cbu = (132201 * THUMBNAIL_SATURATION + 64) / 128;
int cgu = ( 25675 * THUMBNAIL_SATURATION + 64) / 128;
int cgv = ( 53279 * THUMBNAIL_SATURATION + 64) / 128;
int i;
for (i=0; i < 256; i++)
{
tableLY[i] = cly * (i + THUMBNAIL_BRIGHTNESS - 16) + (864 << 16) + 32768;
tableRV[i] = crv * (i - 128);
tableBU[i] = cbu * (i - 128);
tableGU[i] = cgu * (i - 128);
tableGV[i] = cgv * (i - 128);
}
for (i=0; i < 2240; i++)
{
int c = (i < 864) ? 0 : ((i > 1119) ? 255 : (i - 864));
clipR[i] = c << 16;
clipG[i] = c << 8;
clipB[i] = c;
}
}
static void yuvToRgb32( unsigned char *bufy, unsigned char *bufu, unsigned char *bufv,
unsigned int *pixels, int width )
{
for (int i=0; i < width; i++)
{
int l = tableLY[bufy[i]];
pixels[i] = clipR[(l + tableRV[bufv[i]]) >> 16] |
clipG[(l - tableGU[bufu[i]] - tableGV[bufv[i]]) >> 16] |
clipB[(l + tableBU[bufu[i]]) >> 16];
}
}
static inline void scaleLine( unsigned char *src[2], int width,
unsigned char *dst, int scaledWidth,
int scale, int weight, int step, int offset )
{
int a, b, c, d;
int x = (scale / 2) - 32768;
unsigned char *p0 = (src[0] + offset);
unsigned char *p1 = (src[1] + offset);
weight >>= 8;
if (scaledWidth > width)
{
/* Trailing pixels, no horizontal filtering */
c = scaledWidth - (((width << 16) - 32768 - (scale / 2)) / scale);
a = p0[(step * width) - step];
b = p1[(step * width) - step];
a += (128 + (b - a) * weight) >> 8;
scaledWidth -= c;
memset( &dst[scaledWidth], a, c );
/* Leading pixels, no horizontal filtering */
c = (32767 + (scale / 2)) / scale;
a = p0[0];
b = p1[0];
a += (128 + (b - a) * weight) >> 8;
scaledWidth -= c;
memset( dst, a, c );
/* Adjust source and destination */
dst += c;
x += (c * scale);
}
for (int i=0; i < scaledWidth; i++)
{
int xhi = (step == 1) ? (x >> 16)
: ((step == 2) ? (x >> 15) & ~0x1
: (x >> 14) & ~0x3);
int xlo = (x & 0xFFFF) >> 8;
/* Four nearest points for bilinear filtering */
a = p0[xhi];
b = p0[xhi + step];
c = p1[xhi];\
d = p1[xhi + step];
/* Interpolate horizontally */
a = (256 * a) + (b - a) * xlo;
c = (256 * c) + (d - c) * xlo;
/* Interpolate vertically and store bilinear filtered sample */
*(dst++) = ((256 * a) + (c - a) * weight + 32768) >> 16;
x += scale;
}
}
void scaleYuvToRgb32( int width, int height,
unsigned char *base[3], unsigned int pitches[3],
int scaledWidth, int scaledHeight,
unsigned int *pixels, unsigned int bytesPerLine )
{
int chromaWidth = (width + 1) / 2;
int chromaHeight = (height + 1) / 2;
int scaleX = (width << 16) / scaledWidth;
int scaleY = (height << 16) / scaledHeight;
int scaleCX = (scaleX / 2);
int y = (scaleY / 2) - 32768;
// Temporary line buffers (stack)
unsigned char *bufy = (unsigned char *)alloca( scaledWidth );
unsigned char *bufu = (unsigned char *)alloca( scaledWidth );
unsigned char *bufv = (unsigned char *)alloca( scaledWidth );
pthread_once( &once_control, init_once_routine );
for (int i=0; i < scaledHeight; i++)
{
unsigned char *twoy[2], *twou[2], *twov[2];
int y2 = (y / 2) - 32768;
// Calculate luminance scanlines for bilinear filtered scaling
if (y < 0)
{
twoy[0] = twoy[1] = base[0];
}
else if (y >= ((height - 1) << 16))
{
twoy[0] = twoy[1] = base[0] + (height - 1) * pitches[0];
}
else
{
twoy[0] = base[0] + (y >> 16) * pitches[0];
twoy[1] = twoy[0] + pitches[0];
}
// Calculate chrominance scanlines for bilinear filtered scaling
if (y2 < 0)
{
twou[0] = twou[1] = base[1];
twov[0] = twov[1] = base[2];
}
else if (y2 >= ((chromaHeight - 1) << 16))
{
twou[0] = twou[1] = base[1] + (chromaHeight - 1) * pitches[1];
twov[0] = twov[1] = base[2] + (chromaHeight - 1) * pitches[2];
}
else
{
twou[0] = base[1] + (y2 >> 16) * pitches[1];
twov[0] = base[2] + (y2 >> 16) * pitches[2];
twou[1] = twou[0] + pitches[1];
twov[1] = twov[0] + pitches[2];
}
// Bilinear filtered scaling
scaleLine( twoy, width, bufy, scaledWidth, scaleX, (y & 0xFFFF), 1, 0 );
scaleLine( twou, chromaWidth, bufu, scaledWidth, scaleCX, (y2 & 0xFFFF), 1, 0 );
scaleLine( twov, chromaWidth, bufv, scaledWidth, scaleCX, (y2 & 0xFFFF), 1, 0 );
// YUV to RGB32 comnversion
yuvToRgb32( bufy, bufu, bufv, pixels, scaledWidth );
pixels = (unsigned int *)(((char *)pixels) + bytesPerLine);
y += scaleY;
}
}
void scaleYuy2ToRgb32( int width, int height,
unsigned char *base, unsigned int pitch,
int scaledWidth, int scaledHeight,
unsigned int *pixels, unsigned int bytesPerLine )
{
int chromaWidth = (width + 1) / 2;
int scaleX = (width << 16) / scaledWidth;
int scaleY = (height << 16) / scaledHeight;
int scaleCX = (scaleX / 2);
int y = (scaleY / 2) - 32768;
// Temporary line buffers (stack)
unsigned char *bufy = (unsigned char *)alloca( scaledWidth );
unsigned char *bufu = (unsigned char *)alloca( scaledWidth );
unsigned char *bufv = (unsigned char *)alloca( scaledWidth );
pthread_once( &once_control, init_once_routine );
for (int i=0; i < scaledHeight; i++)
{
unsigned char *two[2];
// Calculate scanlines for bilinear filtered scaling
if (y < 0)
{
two[0] = two[1] = base;
}
else if (y >= ((height - 1) << 16))
{
two[0] = two[1] = base + (height - 1) * pitch;
}
else
{
two[0] = base + (y >> 16) * pitch;
two[1] = two[0] + pitch;
}
// Bilinear filtered scaling
scaleLine( two, width, bufy, scaledWidth, scaleX, (y & 0xFFFF), 2, 0 );
scaleLine( two, chromaWidth, bufu, scaledWidth, scaleCX, (y & 0xFFFF), 4, 1 );
scaleLine( two, chromaWidth, bufv, scaledWidth, scaleCX, (y & 0xFFFF), 4, 3 );
// YUV to RGB32 comnversion
yuvToRgb32( bufy, bufu, bufv, pixels, scaledWidth );
pixels = (unsigned int *)(((char *)pixels) + bytesPerLine);
y += scaleY;
}
}