swscale.c

ffmpeg的完整源代码和作者自己写的文档。不但有在Linux的工程哦

/*
 * Copyright (C) 2001-2003 Michael Niedermayer <[e-mail]>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * the C code (not assembly, mmx, ...) of this file can be used
 * under the LGPL license too
 */

/*
  supported Input formats: YV12, I420/IYUV, YUY2, UYVY, BGR32, BGR24, BGR16, BGR15, RGB32, RGB24, Y8/Y800, YVU9/IF09, PAL8
  supported output formats: YV12, I420/IYUV, YUY2, UYVY, {BGR,RGB}{1,4,8,15,16,24,32}, Y8/Y800, YVU9/IF09
  {BGR,RGB}{1,4,8,15,16} support dithering

  unscaled special converters (YV12=I420=IYUV, Y800=Y8)
  YV12 -> {BGR,RGB}{1,4,8,15,16,24,32}
  x -> x
  YUV9 -> YV12
  YUV9/YV12 -> Y800
  Y800 -> YUV9/YV12
  BGR24 -> BGR32 & RGB24 -> RGB32
  BGR32 -> BGR24 & RGB32 -> RGB24
  BGR15 -> BGR16
*/

/*
tested special converters (most are tested actually but i didnt write it down ...)
 YV12 -> BGR16
 YV12 -> YV12
 BGR15 -> BGR16
 BGR16 -> BGR16
 YVU9 -> YV12

untested special converters
  YV12/I420 -> BGR15/BGR24/BGR32 (it is the yuv2rgb stuff, so it should be ok)
  YV12/I420 -> YV12/I420
  YUY2/BGR15/BGR24/BGR32/RGB24/RGB32 -> same format
  BGR24 -> BGR32 & RGB24 -> RGB32
  BGR32 -> BGR24 & RGB32 -> RGB24
  BGR24 -> YV12
*/

#include <inttypes.h>
#include <string.h>
#include <math.h>
#include <stdio.h>
#include <unistd.h>
#include "config.h"
#include <assert.h>
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
#define MAP_ANONYMOUS MAP_ANON
#endif
#endif
#include "swscale.h"
#include "swscale_internal.h"
#include "x86_cpu.h"
#include "bswap.h"
#include "rgb2rgb.h"
#include "libavcodec/opt.h"

#undef MOVNTQ
#undef PAVGB

//#undef HAVE_MMX2
//#define HAVE_3DNOW
//#undef HAVE_MMX
//#undef ARCH_X86
//#define WORDS_BIGENDIAN
#define DITHER1XBPP

#define FAST_BGR2YV12 // use 7 bit coeffs instead of 15bit

#define RET 0xC3 //near return opcode for X86

#ifdef MP_DEBUG
#define ASSERT(x) assert(x);
#else
#define ASSERT(x) ;
#endif

#ifdef M_PI
#define PI M_PI
#else
#define PI 3.14159265358979323846
#endif

#define isSupportedIn(x)    (       \
           (x)==PIX_FMT_YUV420P     \
        || (x)==PIX_FMT_YUVA420P    \
        || (x)==PIX_FMT_YUYV422     \
        || (x)==PIX_FMT_UYVY422     \
        || (x)==PIX_FMT_RGB32       \
        || (x)==PIX_FMT_BGR24       \
        || (x)==PIX_FMT_BGR565      \
        || (x)==PIX_FMT_BGR555      \
        || (x)==PIX_FMT_BGR32       \
        || (x)==PIX_FMT_RGB24       \
        || (x)==PIX_FMT_RGB565      \
        || (x)==PIX_FMT_RGB555      \
        || (x)==PIX_FMT_GRAY8       \
        || (x)==PIX_FMT_YUV410P     \
        || (x)==PIX_FMT_GRAY16BE    \
        || (x)==PIX_FMT_GRAY16LE    \
        || (x)==PIX_FMT_YUV444P     \
        || (x)==PIX_FMT_YUV422P     \
        || (x)==PIX_FMT_YUV411P     \
        || (x)==PIX_FMT_PAL8        \
        || (x)==PIX_FMT_BGR8        \
        || (x)==PIX_FMT_RGB8        \
        || (x)==PIX_FMT_BGR4_BYTE   \
        || (x)==PIX_FMT_RGB4_BYTE   \
        || (x)==PIX_FMT_YUV440P     \
    )
#define isSupportedOut(x)   (       \
           (x)==PIX_FMT_YUV420P     \
        || (x)==PIX_FMT_YUYV422     \
        || (x)==PIX_FMT_UYVY422     \
        || (x)==PIX_FMT_YUV444P     \
        || (x)==PIX_FMT_YUV422P     \
        || (x)==PIX_FMT_YUV411P     \
        || isRGB(x)                 \
        || isBGR(x)                 \
        || (x)==PIX_FMT_NV12        \
        || (x)==PIX_FMT_NV21        \
        || (x)==PIX_FMT_GRAY16BE    \
        || (x)==PIX_FMT_GRAY16LE    \
        || (x)==PIX_FMT_GRAY8       \
        || (x)==PIX_FMT_YUV410P     \
    )
#define isPacked(x)         (       \
           (x)==PIX_FMT_PAL8        \
        || (x)==PIX_FMT_YUYV422     \
        || (x)==PIX_FMT_UYVY422     \
        || isRGB(x)                 \
        || isBGR(x)                 \
    )

#define RGB2YUV_SHIFT 16
#define BY ((int)( 0.098*(1<<RGB2YUV_SHIFT)+0.5))
#define BV ((int)(-0.071*(1<<RGB2YUV_SHIFT)+0.5))
#define BU ((int)( 0.439*(1<<RGB2YUV_SHIFT)+0.5))
#define GY ((int)( 0.504*(1<<RGB2YUV_SHIFT)+0.5))
#define GV ((int)(-0.368*(1<<RGB2YUV_SHIFT)+0.5))
#define GU ((int)(-0.291*(1<<RGB2YUV_SHIFT)+0.5))
#define RY ((int)( 0.257*(1<<RGB2YUV_SHIFT)+0.5))
#define RV ((int)( 0.439*(1<<RGB2YUV_SHIFT)+0.5))
#define RU ((int)(-0.148*(1<<RGB2YUV_SHIFT)+0.5))

extern const int32_t Inverse_Table_6_9[8][4];

/*
NOTES
Special versions: fast Y 1:1 scaling (no interpolation in y direction)

TODO
more intelligent misalignment avoidance for the horizontal scaler
write special vertical cubic upscale version
Optimize C code (yv12 / minmax)
add support for packed pixel yuv input & output
add support for Y8 output
optimize bgr24 & bgr32
add BGR4 output support
write special BGR->BGR scaler
*/

#if defined(ARCH_X86) && defined (CONFIG_GPL)
static uint64_t attribute_used __attribute__((aligned(8))) bF8=       0xF8F8F8F8F8F8F8F8LL;
static uint64_t attribute_used __attribute__((aligned(8))) bFC=       0xFCFCFCFCFCFCFCFCLL;
static uint64_t                __attribute__((aligned(8))) w10=       0x0010001000100010LL;
static uint64_t attribute_used __attribute__((aligned(8))) w02=       0x0002000200020002LL;
static uint64_t attribute_used __attribute__((aligned(8))) bm00001111=0x00000000FFFFFFFFLL;
static uint64_t attribute_used __attribute__((aligned(8))) bm00000111=0x0000000000FFFFFFLL;
static uint64_t attribute_used __attribute__((aligned(8))) bm11111000=0xFFFFFFFFFF000000LL;
static uint64_t attribute_used __attribute__((aligned(8))) bm01010101=0x00FF00FF00FF00FFLL;

static volatile uint64_t attribute_used __attribute__((aligned(8))) b5Dither;
static volatile uint64_t attribute_used __attribute__((aligned(8))) g5Dither;
static volatile uint64_t attribute_used __attribute__((aligned(8))) g6Dither;
static volatile uint64_t attribute_used __attribute__((aligned(8))) r5Dither;

static uint64_t __attribute__((aligned(8))) dither4[2]={
        0x0103010301030103LL,
        0x0200020002000200LL,};

static uint64_t __attribute__((aligned(8))) dither8[2]={
        0x0602060206020602LL,
        0x0004000400040004LL,};

static uint64_t                __attribute__((aligned(8))) b16Mask=   0x001F001F001F001FLL;
static uint64_t attribute_used __attribute__((aligned(8))) g16Mask=   0x07E007E007E007E0LL;
static uint64_t attribute_used __attribute__((aligned(8))) r16Mask=   0xF800F800F800F800LL;
static uint64_t                __attribute__((aligned(8))) b15Mask=   0x001F001F001F001FLL;
static uint64_t attribute_used __attribute__((aligned(8))) g15Mask=   0x03E003E003E003E0LL;
static uint64_t attribute_used __attribute__((aligned(8))) r15Mask=   0x7C007C007C007C00LL;

static uint64_t attribute_used __attribute__((aligned(8))) M24A=      0x00FF0000FF0000FFLL;
static uint64_t attribute_used __attribute__((aligned(8))) M24B=      0xFF0000FF0000FF00LL;
static uint64_t attribute_used __attribute__((aligned(8))) M24C=      0x0000FF0000FF0000LL;

#ifdef FAST_BGR2YV12
static const uint64_t bgr2YCoeff   attribute_used __attribute__((aligned(8))) = 0x000000210041000DULL;
static const uint64_t bgr2UCoeff   attribute_used __attribute__((aligned(8))) = 0x0000FFEEFFDC0038ULL;
static const uint64_t bgr2VCoeff   attribute_used __attribute__((aligned(8))) = 0x00000038FFD2FFF8ULL;
#else
static const uint64_t bgr2YCoeff   attribute_used __attribute__((aligned(8))) = 0x000020E540830C8BULL;
static const uint64_t bgr2UCoeff   attribute_used __attribute__((aligned(8))) = 0x0000ED0FDAC23831ULL;
static const uint64_t bgr2VCoeff   attribute_used __attribute__((aligned(8))) = 0x00003831D0E6F6EAULL;
#endif /* FAST_BGR2YV12 */
static const uint64_t bgr2YOffset  attribute_used __attribute__((aligned(8))) = 0x1010101010101010ULL;
static const uint64_t bgr2UVOffset attribute_used __attribute__((aligned(8))) = 0x8080808080808080ULL;
static const uint64_t w1111        attribute_used __attribute__((aligned(8))) = 0x0001000100010001ULL;
#endif /* defined(ARCH_X86) */

// clipping helper table for C implementations:
static unsigned char clip_table[768];

static SwsVector *sws_getConvVec(SwsVector *a, SwsVector *b);

extern const uint8_t dither_2x2_4[2][8];
extern const uint8_t dither_2x2_8[2][8];
extern const uint8_t dither_8x8_32[8][8];
extern const uint8_t dither_8x8_73[8][8];
extern const uint8_t dither_8x8_220[8][8];

static const char * sws_context_to_name(void * ptr) {
    return "swscaler";
}

#define OFFSET(x) offsetof(SwsContext, x)
#define DEFAULT 0
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM

static const AVOption options[] = {
    { "sws_flags", "scaler/cpu flags", OFFSET(flags), FF_OPT_TYPE_FLAGS, DEFAULT, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "fast_bilinear", "fast bilinear", 0, FF_OPT_TYPE_CONST, SWS_FAST_BILINEAR, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "bilinear", "bilinear", 0, FF_OPT_TYPE_CONST, SWS_BILINEAR, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "bicubic", "bicubic", 0, FF_OPT_TYPE_CONST, SWS_BICUBIC, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "experimental", "experimental", 0, FF_OPT_TYPE_CONST, SWS_X, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "neighbor", "nearest neighbor", 0, FF_OPT_TYPE_CONST, SWS_POINT, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "area", "averaging area", 0, FF_OPT_TYPE_CONST, SWS_AREA, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "bicublin", "luma bicubic, chroma bilinear", 0, FF_OPT_TYPE_CONST, SWS_BICUBLIN, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "gauss", "gaussian", 0, FF_OPT_TYPE_CONST, SWS_GAUSS, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "sinc", "sinc", 0, FF_OPT_TYPE_CONST, SWS_SINC, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "lanczos", "lanczos", 0, FF_OPT_TYPE_CONST, SWS_LANCZOS, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "spline", "natural bicubic spline", 0, FF_OPT_TYPE_CONST, SWS_SPLINE, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "print_info", "print info", 0, FF_OPT_TYPE_CONST, SWS_PRINT_INFO, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "accurate_rnd", "accurate rounding", 0, FF_OPT_TYPE_CONST, SWS_ACCURATE_RND, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "mmx", "MMX SIMD acceleration", 0, FF_OPT_TYPE_CONST, SWS_CPU_CAPS_MMX, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "mmx2", "MMX2 SIMD acceleration", 0, FF_OPT_TYPE_CONST, SWS_CPU_CAPS_MMX2, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "3dnow", "3DNOW SIMD acceleration", 0, FF_OPT_TYPE_CONST, SWS_CPU_CAPS_3DNOW, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "altivec", "AltiVec SIMD acceleration", 0, FF_OPT_TYPE_CONST, SWS_CPU_CAPS_ALTIVEC, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "bfin", "Blackfin SIMD acceleration", 0, FF_OPT_TYPE_CONST, SWS_CPU_CAPS_BFIN, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "full_chroma_int", "full chroma interpolation", 0 , FF_OPT_TYPE_CONST, SWS_FULL_CHR_H_INT, INT_MIN, INT_MAX, VE, "sws_flags" },
    { "full_chroma_inp", "full chroma input", 0 , FF_OPT_TYPE_CONST, SWS_FULL_CHR_H_INP, INT_MIN, INT_MAX, VE, "sws_flags" },
    { NULL }
};

#undef VE
#undef DEFAULT

static AVClass sws_context_class = { "SWScaler", sws_context_to_name, options };

char *sws_format_name(enum PixelFormat format)
{
    switch (format) {
        case PIX_FMT_YUV420P:
            return "yuv420p";
        case PIX_FMT_YUVA420P:
            return "yuva420p";
        case PIX_FMT_YUYV422:
            return "yuyv422";
        case PIX_FMT_RGB24:
            return "rgb24";
        case PIX_FMT_BGR24:
            return "bgr24";
        case PIX_FMT_YUV422P:
            return "yuv422p";
        case PIX_FMT_YUV444P:
            return "yuv444p";
        case PIX_FMT_RGB32:
            return "rgb32";
        case PIX_FMT_YUV410P:
            return "yuv410p";
        case PIX_FMT_YUV411P:
            return "yuv411p";
        case PIX_FMT_RGB565:
            return "rgb565";
        case PIX_FMT_RGB555:
            return "rgb555";
        case PIX_FMT_GRAY16BE:
            return "gray16be";
        case PIX_FMT_GRAY16LE:
            return "gray16le";
        case PIX_FMT_GRAY8:
            return "gray8";
        case PIX_FMT_MONOWHITE:
            return "mono white";
        case PIX_FMT_MONOBLACK:
            return "mono black";
        case PIX_FMT_PAL8:
            return "Palette";
        case PIX_FMT_YUVJ420P:
            return "yuvj420p";
        case PIX_FMT_YUVJ422P:
            return "yuvj422p";
        case PIX_FMT_YUVJ444P:
            return "yuvj444p";
        case PIX_FMT_XVMC_MPEG2_MC:
            return "xvmc_mpeg2_mc";
        case PIX_FMT_XVMC_MPEG2_IDCT:
            return "xvmc_mpeg2_idct";
        case PIX_FMT_UYVY422:
            return "uyvy422";
        case PIX_FMT_UYYVYY411:
            return "uyyvyy411";
        case PIX_FMT_RGB32_1:
            return "rgb32x";
        case PIX_FMT_BGR32_1:
            return "bgr32x";
        case PIX_FMT_BGR32:
            return "bgr32";
        case PIX_FMT_BGR565:
            return "bgr565";
        case PIX_FMT_BGR555:
            return "bgr555";
        case PIX_FMT_BGR8:
            return "bgr8";
        case PIX_FMT_BGR4:
            return "bgr4";
        case PIX_FMT_BGR4_BYTE:
            return "bgr4 byte";
        case PIX_FMT_RGB8:
            return "rgb8";
        case PIX_FMT_RGB4:
            return "rgb4";
        case PIX_FMT_RGB4_BYTE:
            return "rgb4 byte";
        case PIX_FMT_NV12:
            return "nv12";
        case PIX_FMT_NV21:
            return "nv21";
        case PIX_FMT_YUV440P:
            return "yuv440p";
        default:
            return "Unknown format";
    }
}