enset.c

X264的纯C语言的的原码

/*****************************************************************************
 * set: h264 encoder (SPS and PPS init and write)
 *****************************************************************************
 * Copyright (C) 2003 Laurent Aimar
 * $Id: set.c,v 1.1 2004/06/03 19:27:08 fenrir Exp $
 *
 * Authors: Laurent Aimar <[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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

#include <stdio.h>
#include <string.h>
#include <math.h>

#include "common.h"
///#ifndef _MSC_VER
///#include "config.h"
///#endif

static void transpose( uint8_t *buf, int w )
{
    int i, j;
    for( i = 0; i < w; i++ )
        for( j = 0; j < i; j++ )
            XCHG( uint8_t, buf[w*i+j], buf[w*j+i] );
}

static void scaling_list_write( bs_t *s, x264_pps_t *pps, int idx )
{
    const int len = idx<4 ? 16 : 64;
    const int *zigzag = idx<4 ? x264_zigzag_scan4 : x264_zigzag_scan8;
    const uint8_t *list = pps->scaling_list[idx];
    const uint8_t *def_list = (idx==CQM_4IC) ? pps->scaling_list[CQM_4IY]
                            : (idx==CQM_4PC) ? pps->scaling_list[CQM_4PY]
                            : x264_cqm_jvt[idx];
    if( !memcmp( list, def_list, len ) )
        bs_write( s, 1, 0 ); // scaling_list_present_flag
    else if( !memcmp( list, x264_cqm_jvt[idx], len ) )
    {
        bs_write( s, 1, 1 ); // scaling_list_present_flag
        bs_write_se( s, -8 ); // use jvt list
    }
    else
    {
        int j, run;
        bs_write( s, 1, 1 ); // scaling_list_present_flag

        // try run-length compression of trailing values
        for( run = len; run > 1; run-- )
            if( list[zigzag[run-1]] != list[zigzag[run-2]] )
                break;
        if( run < len && len - run < bs_size_se( (int8_t)-list[zigzag[run]] ) )
            run = len;

        for( j = 0; j < run; j++ )
            bs_write_se( s, (int8_t)(list[zigzag[j]] - (j>0 ? list[zigzag[j-1]] : 8)) ); // delta

        if( run < len )
            bs_write_se( s, (int8_t)-list[zigzag[run]] );
    }
}

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

    sps->b_qpprime_y_zero_transform_bypass = param->rc.i_rc_method == X264_RC_CQP && param->rc.i_qp_constant == 0;
    if( sps->b_qpprime_y_zero_transform_bypass )
        sps->i_profile_idc  = PROFILE_HIGH444;
    else if( param->analyse.b_transform_8x8 || param->i_cqm_preset != X264_CQM_FLAT )
        sps->i_profile_idc  = PROFILE_HIGH;
    else if( param->b_cabac || param->i_bframe > 0 )
        sps->i_profile_idc  = PROFILE_MAIN;
    else
        sps->i_profile_idc  = PROFILE_BASELINE;
    sps->i_level_idc = param->i_level_idc;

    sps->b_constraint_set0  = sps->i_profile_idc == PROFILE_BASELINE;
    /* x264 doesn't support the features that are in Baseline and not in Main,
     * namely arbitrary_slice_order and slice_groups. */
    sps->b_constraint_set1  = sps->i_profile_idc <= PROFILE_MAIN;
    /* Never set constraint_set2, it is not necessary and not used in real world. */
    sps->b_constraint_set2  = 0;

    sps->i_log2_max_frame_num = 4;  /* at least 4 */
    while( (1 << sps->i_log2_max_frame_num) <= param->i_keyint_max )
    {
        sps->i_log2_max_frame_num++;
    }
    sps->i_log2_max_frame_num++;    /* just in case */

    sps->i_poc_type = 0;
    if( sps->i_poc_type == 0 )
    {
        sps->i_log2_max_poc_lsb = sps->i_log2_max_frame_num + 1;    /* max poc = 2*frame_num */
    }
    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->b_vui = 1;

    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 ||
        !(param->analyse.inter & X264_ANALYSE_PSUB8x8) )
    {
        sps->b_direct8x8_inference = 1;
    }

    sps->crop.i_left   = 0;
    sps->crop.i_top    = 0;
    sps->crop.i_right  = (- param->i_width)  & 15;
    sps->crop.i_bottom = (- param->i_height) & 15;
    sps->b_crop = sps->crop.i_left  || sps->crop.i_top ||
                  sps->crop.i_right || sps->crop.i_bottom;

    sps->vui.b_aspect_ratio_info_present = 0;
    if( param->vui.i_sar_width > 0 && param->vui.i_sar_height > 0 )
    {
        sps->vui.b_aspect_ratio_info_present = 1;
        sps->vui.i_sar_width = param->vui.i_sar_width;
        sps->vui.i_sar_height= param->vui.i_sar_height;
    }
    
    sps->vui.b_overscan_info_present = ( param->vui.i_overscan ? 1 : 0 );
    if( sps->vui.b_overscan_info_present )
        sps->vui.b_overscan_info = ( param->vui.i_overscan == 2 ? 1 : 0 );
    
    sps->vui.b_signal_type_present = 0;
    sps->vui.i_vidformat = ( param->vui.i_vidformat <= 5 ? param->vui.i_vidformat : 5 );
    sps->vui.b_fullrange = ( param->vui.b_fullrange ? 1 : 0 );
    sps->vui.b_color_description_present = 0;

    sps->vui.i_colorprim = ( param->vui.i_colorprim <=  9 ? param->vui.i_colorprim : 2 );
    sps->vui.i_transfer  = ( param->vui.i_transfer  <= 11 ? param->vui.i_transfer  : 2 );
    sps->vui.i_colmatrix = ( param->vui.i_colmatrix <=  9 ? param->vui.i_colmatrix : 2 );
    if( sps->vui.i_colorprim != 2 ||
        sps->vui.i_transfer  != 2 ||
        sps->vui.i_colmatrix != 2 )
    {
        sps->vui.b_color_description_present = 1;
    }

    if( sps->vui.i_vidformat != 5 ||
        sps->vui.b_fullrange ||
        sps->vui.b_color_description_present )
    {
        sps->vui.b_signal_type_present = 1;
    }
    
    /* FIXME: not sufficient for interlaced video */
    sps->vui.b_chroma_loc_info_present = ( param->vui.i_chroma_loc ? 1 : 0 );
    if( sps->vui.b_chroma_loc_info_present )
    {
        sps->vui.i_chroma_loc_top = param->vui.i_chroma_loc;
        sps->vui.i_chroma_loc_bottom = param->vui.i_chroma_loc;
    }

    sps->vui.b_timing_info_present = 0;
    if( param->i_fps_num > 0 && param->i_fps_den > 0)
    {
        sps->vui.b_timing_info_present = 1;
        sps->vui.i_num_units_in_tick = param->i_fps_den;
        sps->vui.i_time_scale = param->i_fps_num * 2;
        sps->vui.b_fixed_frame_rate = 1;
    }

    sps->vui.i_num_reorder_frames = param->b_bframe_pyramid ? 2 : param->i_bframe ? 1 : 0;
    /* extra slot with pyramid so that we don't have to override the
     * order of forgetting old pictures */
    sps->vui.i_max_dec_frame_buffering =
    sps->i_num_ref_frames = X264_MIN(16, param->i_frame_reference + sps->vui.i_num_reorder_frames + param->b_bframe_pyramid);

    sps->vui.b_bitstream_restriction = 1;
    if( sps->vui.b_bitstream_restriction )
    {
        sps->vui.b_motion_vectors_over_pic_boundaries = 1;
        sps->vui.i_max_bytes_per_pic_denom = 0;
        sps->vui.i_max_bits_per_mb_denom = 0;
        sps->vui.i_log2_max_mv_length_horizontal =
        sps->vui.i_log2_max_mv_length_vertical = (int)(log(param->analyse.i_mv_range*4-1)/log(2)) + 1;
    }
}


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 );

    if( sps->i_profile_idc >= PROFILE_HIGH )
    {
        bs_write_ue( s, 1 ); // chroma_format_idc = 4:2:0
        bs_write_ue( s, 0 ); // bit_depth_luma_minus8
        bs_write_ue( s, 0 ); // bit_depth_chroma_minus8
        bs_write( s, 1, sps->b_qpprime_y_zero_transform_bypass );
        bs_write( s, 1, 0 ); // seq_scaling_matrix_present_flag
    }

    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   / 2 );
        bs_write_ue( s, sps->crop.i_right  / 2 );
        bs_write_ue( s, sps->crop.i_top    / 2 );
        bs_write_ue( s, sps->crop.i_bottom / 2 );