set.c

H.264编码器

/* set: h264 encoder (SPS and SPS init and write) */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "stdint.h"

#include "x264.h"
#include "bs.h"
#include "set.h"

void x264_sps_init( x264_sps_t *sps, int i_id, x264_param_t *param )
{
    sps->i_id               = i_id;
    //sps->i_profile_idc      = PROFILE_EXTENTED;
	sps->i_profile_idc      = PROFILE_BASELINE;

    sps->i_level_idc        = 21;               /* FIXME ? */
    sps->b_constraint_set0  = 0;
    sps->b_constraint_set1  = 0;
    sps->b_constraint_set2  = 0;

    sps->i_log2_max_frame_num = 8;
    sps->i_poc_type = 0;
    if( sps->i_poc_type == 0 )
    {
        sps->i_log2_max_poc_lsb = 8;
    }
    else if( sps->i_poc_type == 1 )
    {
        int i;

        /* FIXME */
        sps->b_delta_pic_order_always_zero = 1;
        sps->i_offset_for_non_ref_pic = 0;
        sps->i_offset_for_top_to_bottom_field = 0;
        sps->i_num_ref_frames_in_poc_cycle = 0;

        for( i = 0; i < sps->i_num_ref_frames_in_poc_cycle; i++ )
        {
            sps->i_offset_for_ref_frame[i] = 0;
        }
    }

    sps->i_num_ref_frames = param->i_frame_reference + 1; /* +1 for 2 ref in B */
    sps->b_gaps_in_frame_num_value_allowed = 0;
    sps->i_mb_width = ( param->i_width + 15 ) / 16;
    sps->i_mb_height= ( param->i_height + 15 )/ 16;
    sps->b_frame_mbs_only = 1;
    sps->b_mb_adaptive_frame_field = 0;
    sps->b_direct8x8_inference = 0;
    if( sps->b_frame_mbs_only == 0 )
    {
        sps->b_direct8x8_inference = 1;
    }

    if( param->i_width % 16 != 0 || param->i_height % 16 != 0 )
    {
        sps->b_crop = 1;
        sps->crop.i_left    = 0;
        sps->crop.i_right   = ( 16 - param->i_width % 16)/2;
        sps->crop.i_top     = 0;
        sps->crop.i_bottom  = ( 16 - param->i_height % 16)/2;
    }
    else
    {
        sps->b_crop = 0;
        sps->crop.i_left    = 0;
        sps->crop.i_right   = 0;
        sps->crop.i_top     = 0;
        sps->crop.i_bottom  = 0;
    }

    if( param->vui.i_sar_width > 0 && param->vui.i_sar_height > 0 )
    {
        int w = param->vui.i_sar_width;
        int h = param->vui.i_sar_height;
        int a = w, b = h;

        while( b != 0 )
        {
            int t = a;

            a = b;
            b = t % b;
        }

        w /= a;
        h /= a;
        while( w > 65535 || h > 65535 )
        {
            w /= 2;
            h /= 2;
        }

        if( w == 0 || h == 0 )
        {
            fprintf( stderr, "x264: cannot create valid sample aspect ratio\n" );
            sps->b_vui = 0;
        }
        else if( w == h )
        {
            fprintf( stderr, "x264: no need for a SAR\n" );
            sps->b_vui = 0;
        }
        else
        {
            fprintf( stderr, "x264: using SAR=%d/%d\n", w, h );
            sps->b_vui = 1;
            sps->vui.i_sar_width = w;
            sps->vui.i_sar_height= h;
        }
    }
    else
    {
        sps->b_vui = 0;
    }
}


void x264_sps_write( bs_t *s, x264_sps_t *sps )
{
    bs_write( s, 8, sps->i_profile_idc );
    bs_write( s, 1, sps->b_constraint_set0 );
    bs_write( s, 1, sps->b_constraint_set1 );
    bs_write( s, 1, sps->b_constraint_set2 );

    bs_write( s, 5, 0 );    /* reserved */

    bs_write( s, 8, sps->i_level_idc );

    bs_write_ue( s, sps->i_id );
    bs_write_ue( s, sps->i_log2_max_frame_num - 4 );
    bs_write_ue( s, sps->i_poc_type );
    if( sps->i_poc_type == 0 )
    {
        bs_write_ue( s, sps->i_log2_max_poc_lsb - 4 );
    }
    else if( sps->i_poc_type == 1 )
    {
        int i;

        bs_write( s, 1, sps->b_delta_pic_order_always_zero );
        bs_write_se( s, sps->i_offset_for_non_ref_pic );
        bs_write_se( s, sps->i_offset_for_top_to_bottom_field );
        bs_write_ue( s, sps->i_num_ref_frames_in_poc_cycle );

        for( i = 0; i < sps->i_num_ref_frames_in_poc_cycle; i++ )
        {
            bs_write_se( s, sps->i_offset_for_ref_frame[i] );
        }
    }
    bs_write_ue( s, sps->i_num_ref_frames );
    bs_write( s, 1, sps->b_gaps_in_frame_num_value_allowed );
    bs_write_ue( s, sps->i_mb_width - 1 );
    bs_write_ue( s, sps->i_mb_height - 1);
    bs_write( s, 1, sps->b_frame_mbs_only );
    if( !sps->b_frame_mbs_only )
    {
        bs_write( s, 1, sps->b_mb_adaptive_frame_field );
    }
    bs_write( s, 1, sps->b_direct8x8_inference );

    bs_write( s, 1, sps->b_crop );
    if( sps->b_crop )
    {
        bs_write_ue( s, sps->crop.i_left );
        bs_write_ue( s, sps->crop.i_right );
        bs_write_ue( s, sps->crop.i_top );
        bs_write_ue( s, sps->crop.i_bottom );
    }

    bs_write( s, 1, sps->b_vui );
    if( sps->b_vui )
    {
        int i;
        static const struct { int w, h; int sar; } sar[] =
        {
            { 1,   1, 1 }, { 12, 11, 2 }, { 10, 11, 3 }, { 16, 11, 4 },
            { 40, 33, 5 }, { 24, 11, 6 }, { 20, 11, 7 }, { 32, 11, 8 },
            { 80, 33, 9 }, { 18, 11, 10}, { 15, 11, 11}, { 64, 33, 12},
            { 160,99, 13}, { 0, 0, -1 }
        };
        bs_write1( s, 1 );      /* aspect_ratio_info_present_flag */
        for( i = 0; sar[i].sar != -1; i++ )
        {
            if( sar[i].w == sps->vui.i_sar_width && sar[i].h == sps->vui.i_sar_height )
                break;
        }
        if( sar[i].sar != -1 )
        {
            bs_write( s, 8, sar[i].sar );
        }
        else
        {
            bs_write( s, 8, 255);   /* aspect_ration_idc (extented) */
            bs_write( s, 16, sps->vui.i_sar_width );
            bs_write( s, 16, sps->vui.i_sar_height );
        }

        bs_write1( s, 0 );      /* overscan_info_present_flag */

        bs_write1( s, 0 );      /* video_signal_type_present_flag */
#if 0
        bs_write( s, 3, 5 );    /* unspecified video format */
        bs_write1( s, 1 );      /* video full range flag */
        bs_write1( s, 0 );      /* colour description present flag */
#endif
        bs_write1( s, 0 );      /* chroma_loc_info_present_flag */
        bs_write1( s, 0 );      /* timing_info_present_flag */
        bs_write1( s, 0 );      /* nal_hrd_parameters_present_flag */
        bs_write1( s, 0 );      /* vcl_hrd_parameters_present_flag */
        bs_write1( s, 0 );      /* pic_struct_present_flag */
        bs_write1( s, 0 );      /* bitstream_restriction_flag */
    }

    bs_rbsp_trailing( s );
}

void x264_pps_init( x264_pps_t *pps, int i_id, x264_param_t *param, x264_sps_t *sps )
{
    pps->i_id = i_id;
    pps->i_sps_id = sps->i_id;
    pps->b_cabac = param->b_cabac;

    pps->b_pic_order = 0;
    pps->i_num_slice_groups = 1;

    if( pps->i_num_slice_groups > 1 )
    {
        int i;

        pps->i_slice_group_map_type = 0;
        if( pps->i_slice_group_map_type == 0 )
        {
            for( i = 0; i < pps->i_num_slice_groups; i++ )
            {
                pps->i_run_length[i] = 1;
            }
        }
        else if( pps->i_slice_group_map_type == 2 )
        {
            for( i = 0; i < pps->i_num_slice_groups; i++ )
            {
                pps->i_top_left[i] = 0;
                pps->i_bottom_right[i] = 0;
            }
        }
        else if( pps->i_slice_group_map_type >= 3 &&
                 pps->i_slice_group_map_type <= 5 )
        {
            pps->b_slice_group_change_direction = 0;
            pps->i_slice_group_change_rate = 0;
        }
        else if( pps->i_slice_group_map_type == 6 )
        {
            pps->i_pic_size_in_map_units = 1;
            for( i = 0; i < pps->i_pic_size_in_map_units; i++ )
            {
                pps->i_slice_group_id[i] = 0;
            }
        }
    }
    pps->i_num_ref_idx_l0_active = 1;
    pps->i_num_ref_idx_l1_active = 1;

    pps->b_weighted_pred = 0;
    pps->b_weighted_bipred = 0;

    pps->i_pic_init_qp = 26;
    pps->i_pic_init_qs = 26;

    pps->i_chroma_qp_index_offset = 0;
#if 0
    if( !param->b_deblocking_filter )
    {
        pps->b_deblocking_filter_control = 1;
    }
    else
    {
        pps->b_deblocking_filter_control = 1;
    }
#endif
    pps->b_deblocking_filter_control = 1;
    pps->b_constrained_intra_pred = 0;
    pps->b_redundant_pic_cnt = 0;
}

void x264_pps_write( bs_t *s, x264_pps_t *pps )
{
    bs_write_ue( s, pps->i_id );
    bs_write_ue( s, pps->i_sps_id );

    bs_write( s, 1, pps->b_cabac );
    bs_write( s, 1, pps->b_pic_order );
    bs_write_ue( s, pps->i_num_slice_groups - 1 );

    if( pps->i_num_slice_groups > 1 )
    {
        int i;

        bs_write_ue( s, pps->i_slice_group_map_type );
        if( pps->i_slice_group_map_type == 0 )
        {
            for( i = 0; i < pps->i_num_slice_groups; i++ )
            {
                bs_write_ue( s, pps->i_run_length[i] - 1 );
            }
        }
        else if( pps->i_slice_group_map_type == 2 )
        {
            for( i = 0; i < pps->i_num_slice_groups; i++ )
            {
                bs_write_ue( s, pps->i_top_left[i] );
                bs_write_ue( s, pps->i_bottom_right[i] );
            }
        }
        else if( pps->i_slice_group_map_type >= 3 &&
                 pps->i_slice_group_map_type <= 5 )
        {
            bs_write( s, 1, pps->b_slice_group_change_direction );
            bs_write_ue( s, pps->b_slice_group_change_direction - 1 );
        }
        else if( pps->i_slice_group_map_type == 6 )
        {
            bs_write_ue( s, pps->i_pic_size_in_map_units - 1 );
            for( i = 0; i < pps->i_pic_size_in_map_units; i++ )
            {
                /* FIXME */
                /* bs_write( s, ceil( log2( pps->i_pic_size_in_map_units +1 ) ),
                 *              pps->i_slice_group_id[i] );
                 */
            }
        }
    }

    bs_write_ue( s, pps->i_num_ref_idx_l0_active - 1 );
    bs_write_ue( s, pps->i_num_ref_idx_l1_active - 1 );
    bs_write( s, 1, pps->b_weighted_pred );
    bs_write( s, 2, pps->b_weighted_bipred );

    bs_write_se( s, pps->i_pic_init_qp - 26 );
    bs_write_se( s, pps->i_pic_init_qs - 26 );
    bs_write_se( s, pps->i_chroma_qp_index_offset );

    bs_write( s, 1, pps->b_deblocking_filter_control );
    bs_write( s, 1, pps->b_constrained_intra_pred );
    bs_write( s, 1, pps->b_redundant_pic_cnt );

    bs_rbsp_trailing( s );
}