common.c

X264的纯C语言的的原码

{
    uint8_t *dst = p_data;
    uint8_t *src = nal->p_payload;
    uint8_t *end = &nal->p_payload[nal->i_payload];

    int i_count = 0;

    /* FIXME this code doesn't check overflow */

    if( b_annexeb )
    {
        /* long nal start code (we always use long ones)*/
        *dst++ = 0x00;
        *dst++ = 0x00;
        *dst++ = 0x00;
        *dst++ = 0x01;
    }

    /* nal header */
    *dst++ = ( 0x00 << 7 ) | ( nal->i_ref_idc << 5 ) | nal->i_type;

    while( src < end )
    {
        if( i_count == 2 && *src <= 0x03 )
        {
            *dst++ = 0x03;
            i_count = 0;
        }
        if( *src == 0 )
        {
            i_count++;
        }
        else
        {
            i_count = 0;
        }
        *dst++ = *src++;
    }
    *pi_data = dst - (uint8_t*)p_data;

    return *pi_data;
}

/****************************************************************************
 * x264_nal_decode:
 ****************************************************************************/
int x264_nal_decode( x264_nal_t *nal, void *p_data, int i_data )
{
    uint8_t *src = p_data;
    uint8_t *end = &src[i_data];
    uint8_t *dst = nal->p_payload;

    nal->i_type    = src[0]&0x1f;
    nal->i_ref_idc = (src[0] >> 5)&0x03;

    src++;

    while( src < end )
    {
        if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00  && src[2] == 0x03 )
        {
            *dst++ = 0x00;
            *dst++ = 0x00;

            src += 3;
            continue;
        }
        *dst++ = *src++;
    }

    nal->i_payload = dst - (uint8_t*)p_data;
    return 0;
}



/****************************************************************************
 * x264_malloc:
 ****************************************************************************/
void *x264_malloc( int i_size )
{
#ifdef SYS_MACOSX
    /* Mac OS X always returns 16 bytes aligned memory */
    return malloc( i_size );
#elif defined( HAVE_MALLOC_H )
    return memalign( 16, i_size );
#else
    uint8_t * buf;
    uint8_t * align_buf;
    buf = (uint8_t *) malloc( i_size + 15 + sizeof( void ** ) +
              sizeof( int ) );
    align_buf = buf + 15 + sizeof( void ** ) + sizeof( int );
    align_buf -= (long) align_buf & 15;
    *( (void **) ( align_buf - sizeof( void ** ) ) ) = buf;
    *( (int *) ( align_buf - sizeof( void ** ) - sizeof( int ) ) ) = i_size;
    return align_buf;
#endif
}

/****************************************************************************
 * x264_free:
 ****************************************************************************/
void x264_free( void *p )
{
    if( p )
    {
#if defined( HAVE_MALLOC_H ) || defined( SYS_MACOSX )
        free( p );
#else
        free( *( ( ( void **) p ) - 1 ) );
#endif
    }
}

/****************************************************************************
 * x264_realloc:
 ****************************************************************************/
void *x264_realloc( void *p, int i_size )
{
#ifdef HAVE_MALLOC_H
    return realloc( p, i_size );
#else
    int       i_old_size = 0;
    uint8_t * p_new;
    if( p )
    {
        i_old_size = *( (int*) ( (uint8_t*) p ) - sizeof( void ** ) -
                         sizeof( int ) );
    }
    p_new = x264_malloc( i_size );
    if( i_old_size > 0 && i_size > 0 )
    {
        memcpy( p_new, p, ( i_old_size < i_size ) ? i_old_size : i_size );
    }
    x264_free( p );
    return p_new;
#endif
}

/****************************************************************************
 * x264_reduce_fraction:
 ****************************************************************************/
void x264_reduce_fraction( int *n, int *d )
{
    int a = *n;
    int b = *d;
    int c;
    if( !a || !b )
        return;
    c = a % b;
    while(c)
    {
	a = b;
	b = c;
	c = a % b;
    }
    *n /= b;
    *d /= b;
}

/****************************************************************************
 * x264_slurp_file:
 ****************************************************************************/
char *x264_slurp_file( const char *filename )
{
    int b_error = 0;
    int i_size;
    char *buf;
    FILE *fh = fopen( filename, "rb" );
    if( !fh )
        return NULL;
    b_error |= fseek( fh, 0, SEEK_END ) < 0;
    b_error |= ( i_size = ftell( fh ) ) <= 0;
    b_error |= fseek( fh, 0, SEEK_SET ) < 0;
    if( b_error )
        return NULL;
    buf = x264_malloc( i_size+2 );
    if( buf == NULL )
        return NULL;
    b_error |= fread( buf, 1, i_size, fh ) != i_size;
    if( buf[i_size-1] != '\n' )
        buf[i_size++] = '\n';
    buf[i_size] = 0;
    fclose( fh );
    if( b_error )
    {
        x264_free( buf );
        return NULL;
    }
    return buf;
}

/****************************************************************************
 * x264_param2string:
 ****************************************************************************/
char *x264_param2string( x264_param_t *p, int b_res )
{
    char *buf = x264_malloc( 1000 );
    char *s = buf;

    if( b_res )
    {
        s += sprintf( s, "%dx%d ", p->i_width, p->i_height );
        s += sprintf( s, "fps=%d/%d ", p->i_fps_num, p->i_fps_den );
    }

///    s += sprintf( s, "cabac=%d", p->b_cabac );
    s += sprintf( s, " ref=%d", p->i_frame_reference );
    s += sprintf( s, " deblock=%d:%d:%d", p->b_deblocking_filter,
                  p->i_deblocking_filter_alphac0, p->i_deblocking_filter_beta );
    s += sprintf( s, " analyse=%#x:%#x", p->analyse.intra, p->analyse.inter );
    s += sprintf( s, " me=%s", x264_motion_est_names[ p->analyse.i_me_method ] );
    s += sprintf( s, " subme=%d", p->analyse.i_subpel_refine );
    s += sprintf( s, " brdo=%d", p->analyse.b_bframe_rdo );
    s += sprintf( s, " mixed_ref=%d", p->analyse.b_mixed_references );
    s += sprintf( s, " me_range=%d", p->analyse.i_me_range );
    s += sprintf( s, " chroma_me=%d", p->analyse.b_chroma_me );
    s += sprintf( s, " trellis=%d", p->analyse.i_trellis );
    s += sprintf( s, " 8x8dct=%d", p->analyse.b_transform_8x8 );
    s += sprintf( s, " cqm=%d", p->i_cqm_preset );
    s += sprintf( s, " chroma_qp_offset=%d", p->analyse.i_chroma_qp_offset );
    s += sprintf( s, " slices=%d", p->i_threads );
    s += sprintf( s, " nr=%d", p->analyse.i_noise_reduction );
    s += sprintf( s, " decimate=%d", p->analyse.b_dct_decimate );

    s += sprintf( s, " bframes=%d", p->i_bframe );
    if( p->i_bframe )
    {
        s += sprintf( s, " b_pyramid=%d b_adapt=%d b_bias=%d direct=%d wpredb=%d bime=%d",
                      p->b_bframe_pyramid, p->b_bframe_adaptive, p->i_bframe_bias,
                      p->analyse.i_direct_mv_pred, p->analyse.b_weighted_bipred,
                      p->analyse.b_bidir_me );
    }

    s += sprintf( s, " keyint=%d keyint_min=%d scenecut=%d",
                  p->i_keyint_max, p->i_keyint_min, p->i_scenecut_threshold );

    s += sprintf( s, " rc=%s", p->rc.i_rc_method == X264_RC_ABR ?
                               ( p->rc.b_stat_read ? "2pass" : p->rc.i_vbv_buffer_size ? "cbr" : "abr" )
                               : p->rc.i_rc_method == X264_RC_CRF ? "crf" : "cqp" );
    if( p->rc.i_rc_method == X264_RC_ABR || p->rc.i_rc_method == X264_RC_CRF )
    {
        if( p->rc.i_rc_method == X264_RC_CRF )
            s += sprintf( s, " crf=%d", p->rc.i_rf_constant );
        else
            s += sprintf( s, " bitrate=%d ratetol=%.1f",
                          p->rc.i_bitrate, p->rc.f_rate_tolerance );
        s += sprintf( s, " rceq='%s' qcomp=%.2f qpmin=%d qpmax=%d qpstep=%d",
                      p->rc.psz_rc_eq, p->rc.f_qcompress,
                      p->rc.i_qp_min, p->rc.i_qp_max, p->rc.i_qp_step );
        if( p->rc.b_stat_read )
            s += sprintf( s, " cplxblur=%.1f qblur=%.1f",
                          p->rc.f_complexity_blur, p->rc.f_qblur );
        if( p->rc.i_vbv_buffer_size )
            s += sprintf( s, " vbv_maxrate=%d vbv_bufsize=%d",
                          p->rc.i_vbv_max_bitrate, p->rc.i_vbv_buffer_size );
    }
    else if( p->rc.i_rc_method == X264_RC_CQP )
        s += sprintf( s, " qp=%d", p->rc.i_qp_constant );
    if( !(p->rc.i_rc_method == X264_RC_CQP && p->rc.i_qp_constant == 0) )
    {
        s += sprintf( s, " ip_ratio=%.2f", p->rc.f_ip_factor );
        if( p->i_bframe )
            s += sprintf( s, " pb_ratio=%.2f", p->rc.f_pb_factor );
        if( p->rc.i_zones )
            s += sprintf( s, " zones" );
    }

    return buf;
}