/* puthdr.c, generation of headers                                          *//* Copyright (C) 1996, MPEG Software Simulation Group. All Rights Reserved. *//* * Disclaimer of Warranty * * These software programs are available to the user without any license fee or * royalty on an "as is" basis.  The MPEG Software Simulation Group disclaims * any and all warranties, whether express, implied, or statuary, including any * implied warranties or merchantability or of fitness for a particular * purpose.  In no event shall the copyright-holder be liable for any * incidental, punitive, or consequential damages of any kind whatsoever * arising from the use of these programs. * * This disclaimer of warranty extends to the user of these programs and user's * customers, employees, agents, transferees, successors, and assigns. * * The MPEG Software Simulation Group does not represent or warrant that the * programs furnished hereunder are free of infringement of any third-party * patents. * * Commercial implementations of MPEG-1 and MPEG-2 video, including shareware, * are subject to royalty fees to patent holders.  Many of these patents are * general enough such that they are unavoidable regardless of implementation * design. * */#include <stdio.h>#include <math.h>#include "config.h"#include "global.h"/* private prototypes */static int frametotc _ANSI_ARGS_((int frame));/* generate sequence header (6.2.2.1, 6.3.3) * * matrix download not implemented */void putseqhdr(){  int i;  alignbits();  putbits(SEQ_START_CODE,32); /* sequence_header_code */  putbits(horizontal_size,12); /* horizontal_size_value */  putbits(vertical_size,12); /* vertical_size_value */  putbits(aspectratio,4); /* aspect_ratio_information */  putbits(frame_rate_code,4); /* frame_rate_code */  putbits((int)ceil(bit_rate/400.0),18); /* bit_rate_value */  putbits(1,1); /* marker_bit */  putbits(vbv_buffer_size,10); /* vbv_buffer_size_value */  putbits(constrparms,1); /* constrained_parameters_flag */  putbits(load_iquant,1); /* load_intra_quantizer_matrix */  if (load_iquant)    for (i=0; i<64; i++)  /* matrices are always downloaded in zig-zag order */      putbits(intra_q[zig_zag_scan[i]],8); /* intra_quantizer_matrix */  putbits(load_niquant,1); /* load_non_intra_quantizer_matrix */  if (load_niquant)    for (i=0; i<64; i++)      putbits(inter_q[zig_zag_scan[i]],8); /* non_intra_quantizer_matrix */}/* generate sequence extension (6.2.2.3, 6.3.5) header (MPEG-2 only) */void putseqext(){  alignbits();  putbits(EXT_START_CODE,32); /* extension_start_code */  putbits(SEQ_ID,4); /* extension_start_code_identifier */  putbits((profile<<4)|level,8); /* profile_and_level_indication */  putbits(prog_seq,1); /* progressive sequence */  putbits(chroma_format,2); /* chroma_format */  putbits(horizontal_size>>12,2); /* horizontal_size_extension */  putbits(vertical_size>>12,2); /* vertical_size_extension */  putbits(((int)ceil(bit_rate/400.0))>>18,12); /* bit_rate_extension */  putbits(1,1); /* marker_bit */  putbits(vbv_buffer_size>>10,8); /* vbv_buffer_size_extension */  putbits(0,1); /* low_delay  -- currently not implemented */  putbits(0,2); /* frame_rate_extension_n */  putbits(0,5); /* frame_rate_extension_d */}/* generate sequence display extension (6.2.2.4, 6.3.6) * * content not yet user setable */void putseqdispext(){  alignbits();  putbits(EXT_START_CODE,32); /* extension_start_code */  putbits(DISP_ID,4); /* extension_start_code_identifier */  putbits(video_format,3); /* video_format */  putbits(1,1); /* colour_description */  putbits(color_primaries,8); /* colour_primaries */  putbits(transfer_characteristics,8); /* transfer_characteristics */  putbits(matrix_coefficients,8); /* matrix_coefficients */  putbits(display_horizontal_size,14); /* display_horizontal_size */  putbits(1,1); /* marker_bit */  putbits(display_vertical_size,14); /* display_vertical_size */}/* output a zero terminated string as user data (6.2.2.2.2, 6.3.4.1) * * string must not emulate start codes */void putuserdata(userdata)char *userdata;{  alignbits();  putbits(USER_START_CODE,32); /* user_data_start_code */  while (*userdata)    putbits(*userdata++,8);}/* generate group of pictures header (6.2.2.6, 6.3.9) * * uses tc0 (timecode of first frame) and frame0 (number of first frame) */void putgophdr(frame,closed_gop)int frame,closed_gop;{  int tc;  alignbits();  putbits(GOP_START_CODE,32); /* group_start_code */  tc = frametotc(tc0+frame);  putbits(tc,25); /* time_code */  putbits(closed_gop,1); /* closed_gop */  putbits(0,1); /* broken_link */}/* convert frame number to time_code * * drop_frame not implemented */static int frametotc(frame)int frame;{  int fps, pict, sec, minute, hour, tc;  fps = (int)(frame_rate+0.5);  pict = frame%fps;  frame = (frame-pict)/fps;  sec = frame%60;  frame = (frame-sec)/60;  minute = frame%60;  frame = (frame-minute)/60;  hour = frame%24;  tc = (hour<<19) | (minute<<13) | (1<<12) | (sec<<6) | pict;  return tc;}/* generate picture header (6.2.3, 6.3.10) */void putpicthdr(){  alignbits();  putbits(PICTURE_START_CODE,32); /* picture_start_code */  calc_vbv_delay();  putbits(temp_ref,10); /* temporal_reference */  putbits(pict_type,3); /* picture_coding_type */  putbits(vbv_delay,16); /* vbv_delay */  if (pict_type==P_TYPE || pict_type==B_TYPE)  {    putbits(0,1); /* full_pel_forward_vector */    if (mpeg1)      putbits(forw_hor_f_code,3);    else      putbits(7,3); /* forward_f_code */  }  if (pict_type==B_TYPE)  {    putbits(0,1); /* full_pel_backward_vector */    if (mpeg1)      putbits(back_hor_f_code,3);    else      putbits(7,3); /* backward_f_code */  }  putbits(0,1); /* extra_bit_picture */}/* generate picture coding extension (6.2.3.1, 6.3.11) * * composite display information (v_axis etc.) not implemented */void putpictcodext(){  alignbits();  putbits(EXT_START_CODE,32); /* extension_start_code */  putbits(CODING_ID,4); /* extension_start_code_identifier */  putbits(forw_hor_f_code,4); /* forward_horizontal_f_code */  putbits(forw_vert_f_code,4); /* forward_vertical_f_code */  putbits(back_hor_f_code,4); /* backward_horizontal_f_code */  putbits(back_vert_f_code,4); /* backward_vertical_f_code */  putbits(dc_prec,2); /* intra_dc_precision */  putbits(pict_struct,2); /* picture_structure */  putbits((pict_struct==FRAME_PICTURE)?topfirst:0,1); /* top_field_first */  putbits(frame_pred_dct,1); /* frame_pred_frame_dct */  putbits(0,1); /* concealment_motion_vectors  -- currently not implemented */  putbits(q_scale_type,1); /* q_scale_type */  putbits(intravlc,1); /* intra_vlc_format */  putbits(altscan,1); /* alternate_scan */  putbits(repeatfirst,1); /* repeat_first_field */  putbits(prog_frame,1); /* chroma_420_type */  putbits(prog_frame,1); /* progressive_frame */  putbits(0,1); /* composite_display_flag */}/* generate sequence_end_code (6.2.2) */void putseqend(){  alignbits();  putbits(SEQ_END_CODE,32);}