i420_rgb.h

video linux conference

            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
        }                                                                     \
        for( i_x = p_vout->output.i_width & 15; i_x--; )                      \
        {                                                                     \
            *p_pic++ = *p_buffer;   p_buffer += *p_offset++;                  \
        }                                                                     \
        p_pic = (void*)((uint8_t*)p_pic + i_right_margin );                   \
    }                                                                         \
    else                                                                      \
    {                                                                         \
        /* No scaling, conversion has been done directly in picture memory.   \
         * Increment of picture pointer to end of line is still needed */     \
        p_pic = (void*)((uint8_t*)p_pic + p_dest->p->i_pitch );               \
    }                                                                         \

/*****************************************************************************
 * SCALE_WIDTH_DITHER: scale a line horizontally for dithered 8 bpp
 *****************************************************************************
 * This macro scales a line using an offset array.
 *****************************************************************************/
#define SCALE_WIDTH_DITHER( CHROMA )                                          \
    if( b_hscale )                                                            \
    {                                                                         \
        /* Horizontal scaling - we can't use a buffer due to dithering */     \
        p_offset = p_offset_start;                                            \
        for( i_x = p_vout->output.i_width / 16; i_x--; )                      \
        {                                                                     \
            CONVERT_4YUV_PIXEL_SCALE( CHROMA )                                \
            CONVERT_4YUV_PIXEL_SCALE( CHROMA )                                \
            CONVERT_4YUV_PIXEL_SCALE( CHROMA )                                \
            CONVERT_4YUV_PIXEL_SCALE( CHROMA )                                \
        }                                                                     \
    }                                                                         \
    else                                                                      \
    {                                                                         \
        for( i_x = p_vout->render.i_width / 16; i_x--;  )                     \
        {                                                                     \
            CONVERT_4YUV_PIXEL( CHROMA )                                      \
            CONVERT_4YUV_PIXEL( CHROMA )                                      \
            CONVERT_4YUV_PIXEL( CHROMA )                                      \
            CONVERT_4YUV_PIXEL( CHROMA )                                      \
        }                                                                     \
    }                                                                         \
    /* Increment of picture pointer to end of line is still needed */         \
    p_pic = (void*)((uint8_t*)p_pic + i_right_margin );                       \
                                                                              \
    /* Increment the Y coordinate in the matrix, modulo 4 */                  \
    i_real_y = (i_real_y + 1) & 0x3;                                          \

/*****************************************************************************
 * SCALE_HEIGHT: handle vertical scaling
 *****************************************************************************
 * This macro handle vertical scaling for a picture. CHROMA may be 420, 422 or
 * 444 for RGB conversion, or 400 for gray conversion. It works for 1, 2, 3
 * and 4 Bpp.
 *****************************************************************************/
#define SCALE_HEIGHT( CHROMA, BPP )                                           \
    /* If line is odd, rewind 4:2:0 U and V samples */                        \
    if( ((CHROMA == 420) || (CHROMA == 422)) && !(i_y & 0x1) )                \
    {                                                                         \
        p_u -= i_chroma_width;                                                \
        p_v -= i_chroma_width;                                                \
    }                                                                         \
                                                                              \
    /*                                                                        \
     * Handle vertical scaling. The current line can be copied or next one    \
     * can be ignored.                                                        \
     */                                                                       \
    switch( i_vscale )                                                        \
    {                                                                         \
    case -1:                             /* vertical scaling factor is < 1 */ \
        while( (i_scale_count -= p_vout->output.i_height) > 0 )               \
        {                                                                     \
            /* Height reduction: skip next source line */                     \
            p_y += p_vout->render.i_width;                                    \
            i_y++;                                                            \
            if( (CHROMA == 420) || (CHROMA == 422) )                          \
            {                                                                 \
                if( i_y & 0x1 )                                               \
                {                                                             \
                    p_u += i_chroma_width;                                    \
                    p_v += i_chroma_width;                                    \
                }                                                             \
            }                                                                 \
            else if( CHROMA == 444 )                                          \
            {                                                                 \
                p_u += p_vout->render.i_width;                                \
                p_v += p_vout->render.i_width;                                \
            }                                                                 \
        }                                                                     \
        i_scale_count += p_vout->render.i_height;                             \
        break;                                                                \
    case 1:                              /* vertical scaling factor is > 1 */ \
        while( (i_scale_count -= p_vout->render.i_height) > 0 )               \
        {                                                                     \
            /* Height increment: copy previous picture line */                \
            p_vout->p_vlc->pf_memcpy( p_pic, p_pic_start,                     \
                                      p_vout->output.i_width * BPP );         \
            p_pic = (void*)((uint8_t*)p_pic + p_dest->p->i_pitch );           \
        }                                                                     \
        i_scale_count += p_vout->output.i_height;                             \
        break;                                                                \
    }                                                                         \

/*****************************************************************************
 * SCALE_HEIGHT_DITHER: handle vertical scaling for dithered 8 bpp
 *****************************************************************************
 * This macro handles vertical scaling for a picture. CHROMA may be 420,
 * 422 or 444 for RGB conversion, or 400 for gray conversion.
 *****************************************************************************/
#define SCALE_HEIGHT_DITHER( CHROMA )                                         \
                                                                              \
    /* If line is odd, rewind 4:2:0 U and V samples */                        \
    if( ((CHROMA == 420) || (CHROMA == 422)) && !(i_y & 0x1) )                \
    {                                                                         \
        p_u -= i_chroma_width;                                                \
        p_v -= i_chroma_width;                                                \
    }                                                                         \
                                                                              \
    /*                                                                        \
     * Handle vertical scaling. The current line can be copied or next one    \
     * can be ignored.                                                        \
     */                                                                       \
                                                                              \
    switch( i_vscale )                                                        \
    {                                                                         \
    case -1:                             /* vertical scaling factor is < 1 */ \
        while( (i_scale_count -= p_vout->output.i_height) > 0 )               \
        {                                                                     \
            /* Height reduction: skip next source line */                     \
            p_y += p_vout->render.i_width;                                    \
            i_y++;                                                            \
            if( (CHROMA == 420) || (CHROMA == 422) )                          \
            {                                                                 \
                if( i_y & 0x1 )                                               \
                {                                                             \
                    p_u += i_chroma_width;                                    \
                    p_v += i_chroma_width;                                    \
                }                                                             \
            }                                                                 \
            else if( CHROMA == 444 )                                          \
            {                                                                 \
                p_u += p_vout->render.i_width;                                \
                p_v += p_vout->render.i_width;                                \
            }                                                                 \
        }                                                                     \
        i_scale_count += p_vout->render.i_height;                             \
        break;                                                                \
    case 1:                              /* vertical scaling factor is > 1 */ \
        while( (i_scale_count -= p_vout->render.i_height) > 0 )               \
        {                                                                     \
            p_y -= p_vout->render.i_width;                                    \
            p_u -= i_chroma_width;                                            \
            p_v -= i_chroma_width;                                            \
            SCALE_WIDTH_DITHER( CHROMA );                                     \
        }                                                                     \
        i_scale_count += p_vout->output.i_height;                             \
        break;                                                                \
    }                                                                         \