libvo/gtf.c

   1 /*
   2  * GTF calculations formulas are taken from GTF_V1R1.xls
   3  * created by ANDY.MORRISH@NSC.COM
   4  *
   5  * copyright (C) 2002 Rudolf Marek <r.marek@assembler.cz>
   6  *
   7  * This file is part of MPlayer.
   8  *
   9  * MPlayer is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * MPlayer is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  22  */
  23
  24 //Version 0.4
  25 #include "config.h"
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <math.h>
  29 #include "gtf.h"
  30
  31 #undef GTF_DEBUG
  32
  33 #ifdef GTF_DEBUG
  34 #define DEBUG_PRINTF(a,b) printf(a,b);
  35 #else
  36 #define DEBUG_PRINTF(a,b)
  37 #endif
  38
  39 static GTF_constants GTF_given_constants = { 3.0,550.0,1,8,1.8,8,40,20,128,600 };
  40
  41 static void GetRoundedConstants(GTF_constants *c)
  42     {
  43     c->Vsync_need = round(GTF_given_constants.Vsync_need);
  44     c->min_Vsync_BP = GTF_given_constants.min_Vsync_BP;
  45     c->min_front_porch = round(GTF_given_constants.min_front_porch);
  46     c->char_cell_granularity = GTF_given_constants.char_cell_granularity;
  47     c->margin_width = GTF_given_constants.margin_width;
  48     c->sync_width = GTF_given_constants.sync_width;
  49     c->c = ((GTF_given_constants.c - GTF_given_constants.j)*(GTF_given_constants.k / 256)) + GTF_given_constants.j;
  50     c->j = GTF_given_constants.j;
  51     c->k = GTF_given_constants.k;
  52     c->m = (GTF_given_constants.k / 256) * GTF_given_constants.m;
  53     }
  54
  55 void GTF_calcTimings(double X,double Y,double freq, int type,
  56                      int want_margins, int want_interlace,struct VesaCRTCInfoBlock *result )
  57 {
  58     GTF_constants   c;
  59     double RR, margin_top, margin_bottom, margin_left, margin_right;
  60     double estimated_H_period,sync_plus_BP,BP,interlace,V_total_lines_field;
  61     double estimated_V_field_rate,actual_H_period,actual_V_field_freq;
  62     double total_active_pixels, ideal_duty_cycle, blanking_time, H_total_pixels;
  63     double H_freq, pixel_freq,actual_V_frame_freq;
  64     double H_sync_start, H_sync_end, H_back_porch, H_front_porch, H_sync_width;
  65     double V_back_porch, V_front_porch, V_sync_start, V_sync_end,V_sync_width;
  66     double ideal_H_period;
  67     GetRoundedConstants(&c);
  68
  69
  70     pixel_freq = RR = freq;
  71
  72     /* DETERMINE IF 1/2 LINE INTERLACE IS PRESENT */
  73
  74     interlace = 0;
  75
  76     if (want_interlace) {
  77     RR = RR * 2;
  78     Y=Y/2;
  79     interlace = 0.5;
  80     }
  81
  82     result->Flags = 0;
  83
  84     if ((Y==300)||(Y==200)||(Y==240))
  85     {
  86     Y*=2;
  87     result->Flags = VESA_CRTC_DOUBLESCAN; /* TODO: check if mode support   */
  88     }
  89
  90     /* DETERMINE NUMBER OF LINES IN V MARGIN */
  91     /* DETERMINE NUMBER OF PIXELS IN H MARGIN [pixels] */
  92
  93     margin_left = margin_right = 0;
  94     margin_top = margin_bottom = 0;
  95
  96     if (want_margins) {
  97         margin_top = margin_bottom = (c.margin_width / 100) * Y;
  98         margin_left = round(( X* c.margin_width/100)/c.char_cell_granularity) \
  99                     * c.char_cell_granularity;
 100     margin_right = margin_left;
 101     DEBUG_PRINTF("margin_left_right : %f\n",margin_right)
 102     DEBUG_PRINTF("margin_top_bottom : %f\n",margin_top)
 103     }
 104
 105     /* FIND TOTAL NUMBER OF ACTIVE PIXELS (IMAGE + MARGIN) [pixels] */
 106
 107     total_active_pixels = margin_left + margin_right + X;
 108     DEBUG_PRINTF("total_active_pixels: %f\n",total_active_pixels)
 109
 110     if (type == GTF_PF)
 111     {
 112     ideal_H_period = ((c.c-100)+(sqrt(((100-c.c)*(100-c.c) )+(0.4*c.m*(total_active_pixels + margin_left + margin_right) / freq))))/2/c.m*1000;
 113
 114     DEBUG_PRINTF("ideal_H_period: %f\n",ideal_H_period)
 115
 116     /* FIND IDEAL BLANKING DUTY CYCLE FROM FORMULA [%] */
 117     ideal_duty_cycle = c.c - (c.m * ideal_H_period /1000);
 118     DEBUG_PRINTF("ideal_duty_cycle: %f\n",ideal_duty_cycle)
 119
 120     /* FIND BLANKING TIME (TO NEAREST CHAR CELL) [pixels] */
 121
 122     blanking_time = round(total_active_pixels * ideal_duty_cycle \
 123                     / (100-ideal_duty_cycle) / (2*c.char_cell_granularity))  \
 124                     * (2*c.char_cell_granularity);
 125     DEBUG_PRINTF("blanking_time : %f\n",blanking_time )
 126
 127     /* FIND TOTAL NUMBER OF PIXELS IN A LINE [pixels] */
 128     H_total_pixels = total_active_pixels + blanking_time ;
 129     DEBUG_PRINTF("H_total_pixels: %f\n",H_total_pixels)
 130     H_freq = freq / H_total_pixels * 1000;
 131     DEBUG_PRINTF("H_freq: %f\n",H_freq)
 132     actual_H_period = 1000 / H_freq;
 133     DEBUG_PRINTF("actual_H_period: %f\n",actual_H_period)
 134     sync_plus_BP = round(H_freq * c.min_Vsync_BP/1000);
 135 //   sync_plus_BP = round( freq / H_total_pixels * c.min_Vsync_BP);
 136
 137     DEBUG_PRINTF("sync_plus_BP: %f\n",sync_plus_BP)
 138
 139     } else if (type == GTF_VF)
 140     {
 141
 142     /* ESTIMATE HORIZ. PERIOD [us] */
 143
 144     estimated_H_period = (( 1/RR ) - c.min_Vsync_BP/1000000 ) /  (Y + (2 * margin_top) + c.min_front_porch + interlace) * 1000000;
 145
 146     DEBUG_PRINTF("estimated_H_period: %f\n",estimated_H_period)
 147
 148     /* FIND NUMBER OF LINES IN (SYNC + BACK PORCH) [lines] */
 149
 150     sync_plus_BP = round( c.min_Vsync_BP / estimated_H_period );
 151     DEBUG_PRINTF("sync_plus_BP: %f\n",sync_plus_BP)
 152
 153     } else if (type == GTF_HF)
 154     {
 155     sync_plus_BP = round(freq * c.min_Vsync_BP/1000);
 156     DEBUG_PRINTF("sync_plus_BP: %f\n",sync_plus_BP)
 157     }
 158
 159
 160
 161     /* FIND TOTAL NUMBER OF LINES IN VERTICAL FIELD */
 162
 163     V_total_lines_field = sync_plus_BP+interlace+margin_bottom+margin_top+Y+c.min_front_porch;
 164     DEBUG_PRINTF("V_total_lines_field : %f\n",V_total_lines_field )
 165
 166     if (type == GTF_VF)
 167     {
 168     /* ESTIMATE VERTICAL FIELD RATE [hz] */
 169
 170     estimated_V_field_rate = 1 / estimated_H_period / V_total_lines_field * 1000000;
 171     DEBUG_PRINTF(" estimated_V_field_rate: %f\n", estimated_V_field_rate)
 172     /* FIND ACTUAL HORIZONTAL PERIOD [us] */
 173
 174     actual_H_period = estimated_H_period / (RR / estimated_V_field_rate);
 175     DEBUG_PRINTF("actual_H_period: %f\n",actual_H_period)
 176     /* FIND ACTUAL VERTICAL FIELD FREQUENCY [Hz] */
 177
 178     actual_V_field_freq = 1 / actual_H_period / V_total_lines_field * 1000000;
 179     DEBUG_PRINTF("actual_V_field_freq: %f\n",actual_V_field_freq)
 180
 181     /* FIND IDEAL BLANKING DUTY CYCLE FROM FORMULA [%] */
 182     ideal_duty_cycle = c.c - (c.m * actual_H_period /1000);
 183     DEBUG_PRINTF("ideal_duty_cycle: %f\n",ideal_duty_cycle)
 184     //if (type == GTF_VF)
 185     //{
 186     //moved
 187     //}
 188     } else if (type == GTF_HF)
 189     {
 190     /* FIND IDEAL BLANKING DUTY CYCLE FROM FORMULA [%] */
 191     ideal_duty_cycle = c.c - (c.m  / freq);
 192     DEBUG_PRINTF("ideal_duty_cycle: %f\n",ideal_duty_cycle)
 193     }
 194
 195     /* FIND BLANKING TIME (TO NEAREST CHAR CELL) [pixels] */
 196
 197     if (!(type == GTF_PF))
 198     {
 199     blanking_time = round(total_active_pixels * ideal_duty_cycle \
 200                     / (100-ideal_duty_cycle) / (2*c.char_cell_granularity))  \
 201                     * (2*c.char_cell_granularity);
 202     DEBUG_PRINTF("blanking_time : %f\n",blanking_time )
 203     }
 204     else
 205 //    if (type == GTF_PF)
 206     {
 207     actual_V_field_freq = H_freq / V_total_lines_field * 1000;
 208     }
 209
 210     if (type == GTF_HF)
 211     {
 212     /* Hz */
 213     actual_V_field_freq = freq / V_total_lines_field * 1000;
 214     DEBUG_PRINTF("actual_V_field_freq: %f\n",actual_V_field_freq)
 215     }
 216
 217
 218     actual_V_frame_freq = actual_V_field_freq;
 219
 220     /* FIND ACTUAL VERTICAL  FRAME FREQUENCY [Hz]*/
 221
 222     if (want_interlace) actual_V_frame_freq = actual_V_field_freq / 2;
 223     DEBUG_PRINTF("actual_V_frame_freq: %f\n",actual_V_frame_freq)
 224
 225 //    V_freq = actual_V_frame_freq;
 226 //    DEBUG_PRINTF("V_freq %f\n",V_freq)
 227
 228
 229     if (!(type == GTF_PF))
 230     {
 231     /* FIND TOTAL NUMBER OF PIXELS IN A LINE [pixels] */
 232     H_total_pixels = total_active_pixels + blanking_time ;
 233     DEBUG_PRINTF("H_total_pixels: %f\n",H_total_pixels)
 234         if (type == GTF_VF)
 235         {
 236         /* FIND PIXEL FREQUENCY [Mhz] */
 237         pixel_freq = H_total_pixels / actual_H_period ;
 238         DEBUG_PRINTF("pixel_freq: %f\n",pixel_freq)
 239         } else if (type == GTF_HF)
 240         {
 241         /* FIND PIXEL FREQUENCY [Mhz] */
 242         pixel_freq = H_total_pixels * freq / 1000 ;
 243         DEBUG_PRINTF("pixel_freq: %f\n",pixel_freq)
 244         actual_H_period = 1000/freq;
 245         }
 246
 247         /* FIND ACTUAL HORIZONTAL FREQUENCY [KHz] */
 248
 249         H_freq = 1000 / actual_H_period;
 250         DEBUG_PRINTF("H_freq %f\n",H_freq)
 251
 252
 253     }
 254
 255     /* FIND NUMBER OF LINES IN BACK PORCH [lines] */
 256
 257     BP = sync_plus_BP - c.Vsync_need;
 258     DEBUG_PRINTF("BP: %f\n",BP)
 259
 260 /*------------------------------------------------------------------------------------------------*/
 261     /* FIND H SYNC WIDTH (TO NEAREST CHAR CELL) */
 262     H_sync_width = round(c.sync_width/100*H_total_pixels/c.char_cell_granularity)*c.char_cell_granularity;
 263     DEBUG_PRINTF("H_sync_width %f\n",H_sync_width)
 264
 265     /* FIND FRONT H PORCH(TO NEAREST CHAR CELL) */
 266     H_front_porch = (blanking_time/2) - H_sync_width;
 267     DEBUG_PRINTF("H_front_porch %f\n",H_front_porch)
 268     /* FIND BACK H PORCH(TO NEAREST CHAR CELL) */
 269     H_back_porch = H_sync_width + H_front_porch;
 270     DEBUG_PRINTF("H_back_porch%f\n",H_back_porch)
 271
 272     H_sync_start = H_total_pixels  - (H_sync_width + H_back_porch);
 273     DEBUG_PRINTF("H_sync_start %f\n",H_sync_start)
 274     H_sync_end = H_total_pixels  - H_back_porch;
 275     DEBUG_PRINTF("H_sync_end %f\n",H_sync_end)
 276
 277     V_back_porch = interlace + BP;
 278     DEBUG_PRINTF("V_back_porch%f\n",V_back_porch)
 279     V_front_porch = interlace + c.min_front_porch;
 280     DEBUG_PRINTF("V_front_porch%f\n",V_front_porch)
 281
 282     V_sync_width = c.Vsync_need;
 283     V_sync_start = V_total_lines_field  - (V_sync_width + V_back_porch);
 284     DEBUG_PRINTF("V_sync_start %f\n",V_sync_start)
 285     V_sync_end = V_total_lines_field  - V_back_porch;
 286     DEBUG_PRINTF("V_sync_end %f\n",V_sync_end)
 287
 288     result->hTotal = H_total_pixels;
 289     result-> hSyncStart  = H_sync_start;  /* Horizontal sync start in pixels */
 290     result-> hSyncEnd = H_sync_end;   /* Horizontal sync end in pixels */
 291     result-> vTotal= V_total_lines_field;     /* Vertical total in lines */
 292     result-> vSyncStart = V_sync_start; /* Vertical sync start in lines */
 293     result-> vSyncEnd = V_sync_end;   /* Vertical sync end in lines */
 294     result->  Flags = (result->Flags)|VESA_CRTC_HSYNC_NEG;      /* Flags (Interlaced, Double Scan etc) */
 295
 296     if (want_interlace)
 297     {
 298     result->Flags = (result->Flags) | VESA_CRTC_INTERLACED;
 299     }
 300
 301     result->  PixelClock = pixel_freq*1000000; /* Pixel clock in units of Hz */
 302     result-> RefreshRate = actual_V_frame_freq*100;/* Refresh rate in units of 0.01 Hz*/
 303
 304     }
 305
 306