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Diffstat (limited to 'libvo/gtf.c')
-rw-r--r-- | libvo/gtf.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/libvo/gtf.c b/libvo/gtf.c new file mode 100644 index 0000000000..07a0887c57 --- /dev/null +++ b/libvo/gtf.c @@ -0,0 +1,297 @@ +/* + * Copyright (C) Rudolf Marek <r.marek@sh.cvut.cz> - Aug 2002 + * + * You can redistribute this file under terms and conditions + * of GNU General Public licence v2. + * + * GTF calculations formulas are taken from GTF_V1R1.xls + * created by ANDY.MORRISH@NSC.COM + */ + +//Version 0.4 +#include <stdio.h> +#include <stdlib.h> +#include <math.h> +#include "gtf.h" + +#undef GTF_DEBUG + +#ifdef GTF_DEBUG +#define DEBUG_PRINTF(a,b) printf(a,b); +#else +#define DEBUG_PRINTF(a,b) +#endif + +static GTF_constants GTF_given_constants = { 3.0,550.0,1,8,1.8,8,40,20,128,600 }; + +static double round(double v) +{ + return floor(v + 0.5); +} + +static void GetRoundedConstants(GTF_constants *c) + { + c->Vsync_need = round(GTF_given_constants.Vsync_need); + c->min_Vsync_BP = GTF_given_constants.min_Vsync_BP; + c->min_front_porch = round(GTF_given_constants.min_front_porch); + c->char_cell_granularity = GTF_given_constants.char_cell_granularity; + c->margin_width = GTF_given_constants.margin_width; + c->sync_width = GTF_given_constants.sync_width; + c->c = ((GTF_given_constants.c - GTF_given_constants.j)*(GTF_given_constants.k / 256)) + GTF_given_constants.j; + c->j = GTF_given_constants.j; + c->k = GTF_given_constants.k; + c->m = (GTF_given_constants.k / 256) * GTF_given_constants.m; + } + +void GTF_calcTimings(double X,double Y,double freq, int type, + int want_margins, int want_interlace,struct VesaCRTCInfoBlock *result ) +{ + GTF_constants c; + double RR, margin_top, margin_bottom, margin_left, margin_right; + double estimated_H_period,sync_plus_BP,BP,interlace,V_total_lines_field; + double estimated_V_field_rate,actual_H_period,actual_V_field_freq; + double total_active_pixels, ideal_duty_cycle, blanking_time, H_total_pixels; + double H_freq, pixel_freq,actual_V_frame_freq; + double H_sync_start, H_sync_end, H_back_porch, H_front_porch, H_sync_width; + double V_back_porch, V_front_porch, V_sync_start, V_sync_end,V_sync_width; + double ideal_H_period; + GetRoundedConstants(&c); + + + pixel_freq = RR = freq; + + /* DETERMINE IF 1/2 LINE INTERLACE IS PRESENT */ + + interlace = 0; + + if (want_interlace) { + RR = RR * 2; + Y=Y/2; + interlace = 0.5; + } + + result->Flags = 0; + + if ((Y==300)||(Y==200)||(Y==240)) + { + Y*=2; + result->Flags = VESA_CRTC_DOUBLESCAN; /* TODO: check if mode support */ + } + + /* DETERMINE NUMBER OF LINES IN V MARGIN */ + /* DETERMINE NUMBER OF PIXELS IN H MARGIN [pixels] */ + + margin_left = margin_right = 0; + margin_top = margin_bottom = 0; + + if (want_margins) { + margin_top = margin_bottom = (c.margin_width / 100) * Y; + margin_left = round(( X* c.margin_width/100)/c.char_cell_granularity) \ + * c.char_cell_granularity; + margin_right = margin_left; + DEBUG_PRINTF("margin_left_right : %f\n",margin_right) + DEBUG_PRINTF("margin_top_bottom : %f\n",margin_top) + } + + /* FIND TOTAL NUMBER OF ACTIVE PIXELS (IMAGE + MARGIN) [pixels] */ + + total_active_pixels = margin_left + margin_right + X; + DEBUG_PRINTF("total_active_pixels: %f\n",total_active_pixels) + + if (type == GTF_PF) + { + 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; + + DEBUG_PRINTF("ideal_H_period: %f\n",ideal_H_period) + + /* FIND IDEAL BLANKING DUTY CYCLE FROM FORMULA [%] */ + ideal_duty_cycle = c.c - (c.m * ideal_H_period /1000); + DEBUG_PRINTF("ideal_duty_cycle: %f\n",ideal_duty_cycle) + + /* FIND BLANKING TIME (TO NEAREST CHAR CELL) [pixels] */ + + blanking_time = round(total_active_pixels * ideal_duty_cycle \ + / (100-ideal_duty_cycle) / (2*c.char_cell_granularity)) \ + * (2*c.char_cell_granularity); + DEBUG_PRINTF("blanking_time : %f\n",blanking_time ) + + /* FIND TOTAL NUMBER OF PIXELS IN A LINE [pixels] */ + H_total_pixels = total_active_pixels + blanking_time ; + DEBUG_PRINTF("H_total_pixels: %f\n",H_total_pixels) + H_freq = freq / H_total_pixels * 1000; + DEBUG_PRINTF("H_freq: %f\n",H_freq) + actual_H_period = 1000 / H_freq; + DEBUG_PRINTF("actual_H_period: %f\n",actual_H_period) + sync_plus_BP = round(H_freq * c.min_Vsync_BP/1000); +// sync_plus_BP = round( freq / H_total_pixels * c.min_Vsync_BP); + + DEBUG_PRINTF("sync_plus_BP: %f\n",sync_plus_BP) + + } else if (type == GTF_VF) + { + + /* ESTIMATE HORIZ. PERIOD [us] */ + + estimated_H_period = (( 1/RR ) - c.min_Vsync_BP/1000000 ) / (Y + (2 * margin_top) + c.min_front_porch + interlace) * 1000000; + + DEBUG_PRINTF("estimated_H_period: %f\n",estimated_H_period) + + /* FIND NUMBER OF LINES IN (SYNC + BACK PORCH) [lines] */ + + sync_plus_BP = round( c.min_Vsync_BP / estimated_H_period ); + DEBUG_PRINTF("sync_plus_BP: %f\n",sync_plus_BP) + + } else if (type == GTF_HF) + { + sync_plus_BP = round(freq * c.min_Vsync_BP/1000); + DEBUG_PRINTF("sync_plus_BP: %f\n",sync_plus_BP) + } + + + + /* FIND TOTAL NUMBER OF LINES IN VERTICAL FIELD */ + + V_total_lines_field = sync_plus_BP+interlace+margin_bottom+margin_top+Y+c.min_front_porch; + DEBUG_PRINTF("V_total_lines_field : %f\n",V_total_lines_field ) + + if (type == GTF_VF) + { + /* ESTIMATE VERTICAL FIELD RATE [hz] */ + + estimated_V_field_rate = 1 / estimated_H_period / V_total_lines_field * 1000000; + DEBUG_PRINTF(" estimated_V_field_rate: %f\n", estimated_V_field_rate) + /* FIND ACTUAL HORIZONTAL PERIOD [us] */ + + actual_H_period = estimated_H_period / (RR / estimated_V_field_rate); + DEBUG_PRINTF("actual_H_period: %f\n",actual_H_period) + /* FIND ACTUAL VERTICAL FIELD FREQUENCY [Hz] */ + + actual_V_field_freq = 1 / actual_H_period / V_total_lines_field * 1000000; + DEBUG_PRINTF("actual_V_field_freq: %f\n",actual_V_field_freq) + + /* FIND IDEAL BLANKING DUTY CYCLE FROM FORMULA [%] */ + ideal_duty_cycle = c.c - (c.m * actual_H_period /1000); + DEBUG_PRINTF("ideal_duty_cycle: %f\n",ideal_duty_cycle) + //if (type == GTF_VF) + //{ + //moved + //} + } else if (type == GTF_HF) + { + /* FIND IDEAL BLANKING DUTY CYCLE FROM FORMULA [%] */ + ideal_duty_cycle = c.c - (c.m / freq); + DEBUG_PRINTF("ideal_duty_cycle: %f\n",ideal_duty_cycle) + } + + /* FIND BLANKING TIME (TO NEAREST CHAR CELL) [pixels] */ + + if (!(type == GTF_PF)) + { + blanking_time = round(total_active_pixels * ideal_duty_cycle \ + / (100-ideal_duty_cycle) / (2*c.char_cell_granularity)) \ + * (2*c.char_cell_granularity); + DEBUG_PRINTF("blanking_time : %f\n",blanking_time ) + } + else +// if (type == GTF_PF) + { + actual_V_field_freq = H_freq / V_total_lines_field * 1000; + } + + if (type == GTF_HF) + { + /* Hz */ + actual_V_field_freq = freq / V_total_lines_field * 1000; + DEBUG_PRINTF("actual_V_field_freq: %f\n",actual_V_field_freq) + } + + + actual_V_frame_freq = actual_V_field_freq; + + /* FIND ACTUAL VERTICAL FRAME FREQUENCY [Hz]*/ + + if (want_interlace) actual_V_frame_freq = actual_V_field_freq / 2; + DEBUG_PRINTF("actual_V_frame_freq: %f\n",actual_V_frame_freq) + +// V_freq = actual_V_frame_freq; +// DEBUG_PRINTF("V_freq %f\n",V_freq) + + + if (!(type == GTF_PF)) + { + /* FIND TOTAL NUMBER OF PIXELS IN A LINE [pixels] */ + H_total_pixels = total_active_pixels + blanking_time ; + DEBUG_PRINTF("H_total_pixels: %f\n",H_total_pixels) + if (type == GTF_VF) + { + /* FIND PIXEL FREQUENCY [Mhz] */ + pixel_freq = H_total_pixels / actual_H_period ; + DEBUG_PRINTF("pixel_freq: %f\n",pixel_freq) + } else if (type == GTF_HF) + { + /* FIND PIXEL FREQUENCY [Mhz] */ + pixel_freq = H_total_pixels * freq / 1000 ; + DEBUG_PRINTF("pixel_freq: %f\n",pixel_freq) + actual_H_period = 1000/freq; + } + + /* FIND ACTUAL HORIZONTAL FREQUENCY [KHz] */ + + H_freq = 1000 / actual_H_period; + DEBUG_PRINTF("H_freq %f\n",H_freq) + + + } + + /* FIND NUMBER OF LINES IN BACK PORCH [lines] */ + + BP = sync_plus_BP - c.Vsync_need; + DEBUG_PRINTF("BP: %f\n",BP) + +/*------------------------------------------------------------------------------------------------*/ + /* FIND H SYNC WIDTH (TO NEAREST CHAR CELL) */ + H_sync_width = round(c.sync_width/100*H_total_pixels/c.char_cell_granularity)*c.char_cell_granularity; + DEBUG_PRINTF("H_sync_width %f\n",H_sync_width) + + /* FIND FRONT H PORCH(TO NEAREST CHAR CELL) */ + H_front_porch = (blanking_time/2) - H_sync_width; + DEBUG_PRINTF("H_front_porch %f\n",H_front_porch) + /* FIND BACK H PORCH(TO NEAREST CHAR CELL) */ + H_back_porch = H_sync_width + H_front_porch; + DEBUG_PRINTF("H_back_porch%f\n",H_back_porch) + + H_sync_start = H_total_pixels - (H_sync_width + H_back_porch); + DEBUG_PRINTF("H_sync_start %f\n",H_sync_start) + H_sync_end = H_total_pixels - H_back_porch; + DEBUG_PRINTF("H_sync_end %f\n",H_sync_end) + + V_back_porch = interlace + BP; + DEBUG_PRINTF("V_back_porch%f\n",V_back_porch) + V_front_porch = interlace + c.min_front_porch; + DEBUG_PRINTF("V_front_porch%f\n",V_front_porch) + + V_sync_width = c.Vsync_need; + V_sync_start = V_total_lines_field - (V_sync_width + V_back_porch); + DEBUG_PRINTF("V_sync_start %f\n",V_sync_start) + V_sync_end = V_total_lines_field - V_back_porch; + DEBUG_PRINTF("V_sync_end %f\n",V_sync_end) + + result->hTotal = H_total_pixels; + result-> hSyncStart = H_sync_start; /* Horizontal sync start in pixels */ + result-> hSyncEnd = H_sync_end; /* Horizontal sync end in pixels */ + result-> vTotal= V_total_lines_field; /* Vertical total in lines */ + result-> vSyncStart = V_sync_start; /* Vertical sync start in lines */ + result-> vSyncEnd = V_sync_end; /* Vertical sync end in lines */ + result-> Flags = (result->Flags)|VESA_CRTC_HSYNC_NEG; /* Flags (Interlaced, Double Scan etc) */ + + if (want_interlace) + { + result->Flags = (result->Flags) | VESA_CRTC_INTERLACED; + } + + result-> PixelClock = pixel_freq*1000000; /* Pixel clock in units of Hz */ + result-> RefreshRate = actual_V_frame_freq*100;/* Refresh rate in units of 0.01 Hz*/ + + } + + |