swscale.c

VLC Player Source Code

/*****************************************************************************
 * swscale.c: scaling and chroma conversion using libswscale
 *****************************************************************************
 * Copyright (C) 1999-2008 the VideoLAN team
 * $Id: 81a963259dad1893873d3414feecca226d47e8d1 $
 *
 * Authors: Laurent Aimar <[e-mail]>
 *          Gildas Bazin <[e-mail]>
 *
 * 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.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_vout.h>
#include <vlc_filter.h>

#ifdef HAVE_LIBSWSCALE_SWSCALE_H
#   include <libswscale/swscale.h>
#elif defined(HAVE_FFMPEG_SWSCALE_H)
#   include <ffmpeg/swscale.h>
#endif

/* Gruikkkkkkkkkk!!!!! */
#include "../codec/avcodec/chroma.h"

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
static int  OpenScaler( vlc_object_t * );
static void CloseScaler( vlc_object_t * );

#define SCALEMODE_TEXT N_("Scaling mode")
#define SCALEMODE_LONGTEXT N_("Scaling mode to use.")

static const int pi_mode_values[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
const char *const ppsz_mode_descriptions[] =
{ N_("Fast bilinear"), N_("Bilinear"), N_("Bicubic (good quality)"),
  N_("Experimental"), N_("Nearest neighbour (bad quality)"),
  N_("Area"), N_("Luma bicubic / chroma bilinear"), N_("Gauss"),
  N_("SincR"), N_("Lanczos"), N_("Bicubic spline") };

vlc_module_begin();
    set_description( N_("Video scaling filter") );
    set_capability( "video filter2", 150 );
    set_category( CAT_VIDEO );
    set_subcategory( SUBCAT_VIDEO_VFILTER );
    set_callbacks( OpenScaler, CloseScaler );
    add_integer( "swscale-mode", 2, NULL, SCALEMODE_TEXT, SCALEMODE_LONGTEXT, true );
        change_integer_list( pi_mode_values, ppsz_mode_descriptions, NULL );
vlc_module_end();

/* Version checking */
#if LIBSWSCALE_VERSION_INT >= ((0<<16)+(5<<8)+0)
/****************************************************************************
 * Local prototypes
 ****************************************************************************/

void *( *swscale_fast_memcpy )( void *, const void *, size_t );

/**
 * Internal swscale filter structure.
 */
struct filter_sys_t
{
    SwsFilter *p_src_filter;
    SwsFilter *p_dst_filter;
    int i_cpu_mask, i_sws_flags;

    video_format_t fmt_in;
    video_format_t fmt_out;

    struct SwsContext *ctx;
    struct SwsContext *ctxA;
    picture_t *p_src_a;
    picture_t *p_dst_a;
    int i_extend_factor;
    picture_t *p_src_e;
    picture_t *p_dst_e;
    bool b_add_a;
};

static picture_t *Filter( filter_t *, picture_t * );
static int  Init( filter_t * );
static void Clean( filter_t * );

typedef struct
{
    int  i_fmti;
    int  i_fmto;
    bool b_has_a;
    bool b_add_a;
    int  i_sws_flags;
} ScalerConfiguration;

static int GetParameters( ScalerConfiguration *,
                          const video_format_t *p_fmti,
                          const video_format_t *p_fmto,
                          int i_sws_flags_default );

static int GetSwsCpuMask(void);

/* SwScaler point resize quality seems really bad, let our scale module do it
 * (change it to true to try) */
#define ALLOW_YUVP (false)
/* SwScaler does not like too small picture */
#define MINIMUM_WIDTH (16)

/* XXX is it always 3 even for BIG_ENDIAN (blend.c seems to think so) ? */
#define OFFSET_A (3)

/*****************************************************************************
 * OpenScaler: probe the filter and return score
 *****************************************************************************/
static int OpenScaler( vlc_object_t *p_this )
{
    filter_t *p_filter = (filter_t*)p_this;
    filter_sys_t *p_sys;

    int i_sws_mode;

    float sws_lum_gblur = 0.0, sws_chr_gblur = 0.0;
    int sws_chr_vshift = 0, sws_chr_hshift = 0;
    float sws_chr_sharpen = 0.0, sws_lum_sharpen = 0.0;

    if( GetParameters( NULL,
                       &p_filter->fmt_in.video,
                       &p_filter->fmt_out.video, 0 ) )
        return VLC_EGENERIC;

    /* */
    p_filter->pf_video_filter = Filter;
    /* Allocate the memory needed to store the decoder's structure */
    if( ( p_filter->p_sys = p_sys = malloc(sizeof(filter_sys_t)) ) == NULL )
        return VLC_ENOMEM;

    /* FIXME pointer assignment may not be atomic */
    swscale_fast_memcpy = vlc_memcpy;

    /* Set CPU capabilities */
    p_sys->i_cpu_mask = GetSwsCpuMask();

    /* */
    i_sws_mode = var_CreateGetInteger( p_filter, "swscale-mode" );
    switch( i_sws_mode )
    {
    case 0:  p_sys->i_sws_flags = SWS_FAST_BILINEAR; break;
    case 1:  p_sys->i_sws_flags = SWS_BILINEAR; break;
    case 2:  p_sys->i_sws_flags = SWS_BICUBIC; break;
    case 3:  p_sys->i_sws_flags = SWS_X; break;
    case 4:  p_sys->i_sws_flags = SWS_POINT; break;
    case 5:  p_sys->i_sws_flags = SWS_AREA; break;
    case 6:  p_sys->i_sws_flags = SWS_BICUBLIN; break;
    case 7:  p_sys->i_sws_flags = SWS_GAUSS; break;
    case 8:  p_sys->i_sws_flags = SWS_SINC; break;
    case 9:  p_sys->i_sws_flags = SWS_LANCZOS; break;
    case 10: p_sys->i_sws_flags = SWS_SPLINE; break;
    default: p_sys->i_sws_flags = SWS_BICUBIC; i_sws_mode = 2; break;
    }

    p_sys->p_src_filter =
        sws_getDefaultFilter( sws_lum_gblur, sws_chr_gblur,
                              sws_lum_sharpen, sws_chr_sharpen,
                              sws_chr_hshift, sws_chr_vshift, 0 );
    p_sys->p_dst_filter = NULL;

    /* Misc init */
    p_sys->ctx = NULL;
    p_sys->ctxA = NULL;
    p_sys->p_src_a = NULL;
    p_sys->p_dst_a = NULL;
    p_sys->p_src_e = NULL;
    p_sys->p_dst_e = NULL;
    memset( &p_sys->fmt_in,  0, sizeof(p_sys->fmt_in) );
    memset( &p_sys->fmt_out, 0, sizeof(p_sys->fmt_out) );

    if( Init( p_filter ) )
    {
        if( p_sys->p_src_filter )
            sws_freeFilter( p_sys->p_src_filter );
        free( p_sys );
        return VLC_EGENERIC;
    }

    msg_Dbg( p_filter, "%ix%i chroma: %4.4s -> %ix%i chroma: %4.4s with scaling using %s",
             p_filter->fmt_in.video.i_width, p_filter->fmt_in.video.i_height,
             (char *)&p_filter->fmt_in.video.i_chroma,
             p_filter->fmt_out.video.i_width, p_filter->fmt_out.video.i_height,
             (char *)&p_filter->fmt_out.video.i_chroma,
             ppsz_mode_descriptions[i_sws_mode] );

    return VLC_SUCCESS;
}

/*****************************************************************************
 * CloseFilter: clean up the filter
 *****************************************************************************/
static void CloseScaler( vlc_object_t *p_this )
{
    filter_t *p_filter = (filter_t*)p_this;
    filter_sys_t *p_sys = p_filter->p_sys;

    Clean( p_filter );
    if( p_sys->p_src_filter )
        sws_freeFilter( p_sys->p_src_filter );
    free( p_sys );
}

/*****************************************************************************
 * Helpers
 *****************************************************************************/
static int GetSwsCpuMask(void)
{
    const unsigned int i_cpu = vlc_CPU();
    int i_sws_cpu = 0;

    if( i_cpu & CPU_CAPABILITY_MMX )
        i_sws_cpu |= SWS_CPU_CAPS_MMX;
#if (LIBSWSCALE_VERSION_INT >= ((0<<16)+(5<<8)+0))
    if( i_cpu & CPU_CAPABILITY_MMXEXT )
        i_sws_cpu |= SWS_CPU_CAPS_MMX2;
#endif
    if( i_cpu & CPU_CAPABILITY_3DNOW )
        i_sws_cpu |= SWS_CPU_CAPS_3DNOW;

    if( i_cpu & CPU_CAPABILITY_ALTIVEC )
        i_sws_cpu |= SWS_CPU_CAPS_ALTIVEC;

    return i_sws_cpu;
}
static bool IsFmtSimilar( const video_format_t *p_fmt1, const video_format_t *p_fmt2 )
{
    return p_fmt1->i_chroma == p_fmt2->i_chroma &&
           p_fmt1->i_width  == p_fmt2->i_width &&
           p_fmt1->i_height == p_fmt2->i_height;
}

static int GetParameters( ScalerConfiguration *p_cfg,
                          const video_format_t *p_fmti,
                          const video_format_t *p_fmto,
                          int i_sws_flags_default )
{
    int i_fmti = -1;
    int i_fmto = -1;

    bool b_has_ai = false;
    bool b_has_ao = false;
    int i_sws_flags = i_sws_flags_default;

    GetFfmpegChroma( &i_fmti, *p_fmti );
    GetFfmpegChroma( &i_fmto, *p_fmto );

    if( p_fmti->i_chroma == p_fmto->i_chroma )
    {
        if( p_fmti->i_chroma == VLC_FOURCC( 'Y', 'U', 'V', 'P' ) && ALLOW_YUVP )
        {
            i_fmti = i_fmto = PIX_FMT_GRAY8;
            i_sws_flags = SWS_POINT;
        }
    }

    if( p_fmti->i_chroma == VLC_FOURCC( 'Y', 'U', 'V', 'A' ) )
    {
        i_fmti = PIX_FMT_YUV444P;
        b_has_ai = true;
    }
    else if( p_fmti->i_chroma == VLC_FOURCC( 'R', 'G', 'B', 'A' ) )
    {
        i_fmti = PIX_FMT_BGR32;
        b_has_ai = true;
    }

    if( p_fmto->i_chroma == VLC_FOURCC( 'Y', 'U', 'V', 'A' ) )
    {
        i_fmto = PIX_FMT_YUV444P;
        b_has_ao = true;
    }