libvo/spuenc.c

   1 /*
   2  * subpic_encode.c - encodes a pixmap with RLE
   3  *
   4  * Copyright (C) 2000   Alejandro J. Cura <alecu@protocultura.net>
   5  *
   6  * (modified a bit to work with the dxr3 driver...4/2/2002 cg)
   7  *
   8  * Based on the hard work of:
   9  *
  10  *   Samuel Hocevar <sam@via.ecp.fr> and Michel Lespinasse <walken@via.ecp.fr>
  11  *
  12  * This file is part of MPlayer.
  13  *
  14  * MPlayer is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * MPlayer is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License along
  25  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  26  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  27  */
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include "unistd.h"
  32 #include "spuenc.h"
  33
  34 static void
  35 encode_do_control(int x,int y, encodedata* ed, pixbuf* pb) {
  36         int controlstart= ed->count;
  37         int x1;
  38         int i;
  39         unsigned int top, left, bottom, right;
  40
  41         top= 450 - pb->y/2;
  42         left=(720 / 2) - (pb->x / 2);
  43         top= 32;//this forces the first bit to be visible on a TV
  44         left= 32;//you could actually pass in x/y and do some nice
  45                  //calculations for making it look right...
  46         bottom= top + pb->y - 1;
  47         right= left + pb->x - 1;
  48
  49 /* the format of this is well described by a page:
  50  * http://members.aol.com/mpucoder/DVD/spu.html
  51  *
  52  * note I changed the layout of commands to turn off the subpic as the
  53  * first command, and then turn on the new subpic...this is so we can
  54  * leave the subpic on for an arbitrary ammount of time as controlled by
  55  * mplayer (ie when we turn on the subpic we don't know how long it should
  56  * stay on when using mplayer).
  57  * with this layout we turn off the last subpic as we are turning on the
  58  * new one.
  59  * The original hd it turn on the subpic, and delay the turn off command using
  60  * the durration/delay feature.
  61  * */
  62         /* start at x0+2*/
  63         i= controlstart;
  64         /* display duration... */
  65 //      ed->data[i++]= 0x00;
  66 //      ed->data[i++]= 0x00; //durration before turn off command occurs
  67                              //in 90000/1024 units
  68
  69         /* x1 */
  70 //      x1=i+4;
  71 //      ed->data[i++]= x1 >> 8;//location of next command block
  72 //      ed->data[i++]= x1 & 0xff;
  73         /* finish it */
  74 //      ed->data[i++]= 0x02;//turn off command
  75 //      ed->data[i++]= 0xff;//end of command block
  76         x1= i; //marker for last command block address
  77
  78         /* display duration... */
  79         ed->data[i++]= 0x00;
  80         ed->data[i++]= 0x00; //durration before turn on command occurs
  81                              //in 90000/1024 units
  82         /* x1 */
  83         ed->data[i++]= x1 >> 8;  //since this is the last command block, this
  84         ed->data[i++]= x1 & 0xff;//points back to itself
  85
  86
  87         /* 0x01: start displaying */
  88         ed->data[i++]= 0x01;
  89
  90         /* 0x03: palette info */
  91         ed->data[i++]= 0x03;
  92         ed->data[i++]= 0x08;
  93         ed->data[i++]= 0x7f;
  94 /*
  95  * The palette is a coded index (one of 16) 0 is black, 0xf is white
  96  * (unless you screw with the default palette)
  97  * for what I am doing I only use white.
  98  * 7 is lt grey, and 8 is dk grey...
  99  * */
 100         /* 0x04: transparency info (reversed) */
 101         ed->data[i++]= 0x04;
 102         ed->data[i++]= 0xFF;//change the opacity values of the color entries
 103         ed->data[i++]= 0xF0;//say if you wanted white text on a black backround
 104                             //note you will have to work harder, by finding the
 105         //bounding box of the text, and use a non transparent black palette
 106         // entry to fill the backround with, (say color 1 instead of 0)
 107
 108         /* 0x05: coordinates */
 109         ed->data[i++]= 0x05;
 110         ed->data[i++]= left >> 4;
 111         ed->data[i++]= ((left&0xf)<<4)+(right>>8);
 112         ed->data[i++]= (right&0xff);
 113         ed->data[i++]= top >> 4;
 114         ed->data[i++]= ((top&0xf)<<4)+(bottom>>8);
 115         ed->data[i++]= (bottom&0xff);
 116
 117         /* 0x06: both fields' offsets */
 118         ed->data[i++]= 0x06;
 119         ed->data[i++]= 0x00;
 120         ed->data[i++]= 0x04;
 121         ed->data[i++]= ed->oddstart >> 8;
 122         ed->data[i++]= ed->oddstart & 0xff;
 123
 124         /* 0xFF: end sequence */
 125         ed->data[i++]= 0xFF;
 126         if(! i&1 ) {
 127                 ed->data[i++]= 0xff;
 128         }
 129
 130         /* x0 */
 131         ed->data[2]= (controlstart) >> 8;
 132         ed->data[3]= (controlstart) & 0xff;
 133
 134         /* packet size */
 135         ed->data[0]= i >> 8;
 136         ed->data[1]= i & 0xff;
 137
 138         ed->count= i;
 139 }
 140
 141 static void
 142 encode_put_nibble( encodedata* ed, unsigned char nibble ) {
 143         if( ed->nibblewaiting ) {
 144                 ed->data[ed->count++]|= nibble;
 145                 ed->nibblewaiting= 0;
 146         } else {
 147                 ed->data[ed->count]= nibble<<4;
 148                 ed->nibblewaiting= 1;
 149         }
 150 }
 151
 152 static void
 153 encode_pixels( encodedata* ed, int color, int number ) {
 154         if(number > 3) {
 155                 if(number > 15) {
 156                         encode_put_nibble( ed, 0 );
 157                         if(number > 63) {
 158                                 encode_put_nibble( ed, (number & 0xC0)>>6 );
 159                         }
 160                 }
 161                 encode_put_nibble( ed, (number & 0x3C)>>2 );
 162         }
 163         encode_put_nibble( ed, ((number & 0xF)<<2) | color);
 164 }
 165
 166 static void
 167 encode_eol( encodedata* ed ) {
 168         if( ed->nibblewaiting ) {
 169                 ed->count++;
 170                 ed->nibblewaiting= 0;
 171         }
 172         ed->data[ed->count++]= 0x00;
 173         ed->data[ed->count++]= 0x00;
 174 }
 175
 176 static void
 177 encode_do_row( encodedata* ed, pixbuf* pb, int row ) {
 178         int i= 0;
 179         unsigned char* pix= pb->pixels + row * pb->x;
 180         int color= *pix;
 181         int n= 0; /* the number of pixels of this color */
 182
 183         while( i++ < pb->x ) {
 184                 /* FIXME: watch this space for EOL */
 185                 if( *pix != color || n == 255 ) {
 186                         encode_pixels( ed, color, n );
 187                         color= *pix;
 188                         n= 1;
 189                 } else {
 190                         n++;
 191                 }
 192                 pix++;
 193         }
 194
 195         /* this small optimization: (n>63) can save up to two bytes per line
 196          * I wonder if this is compatible with all the hardware... */
 197         if( color == 0 && n > 63 ) {
 198                 encode_eol( ed );
 199         } else {
 200                 encode_pixels( ed, color, n );
 201         }
 202
 203         if( ed->nibblewaiting ) {
 204                 ed->count++;
 205                 ed->nibblewaiting= 0;
 206         }
 207 }
 208
 209
 210 void
 211 pixbuf_encode_rle(int x, int y, int w, int h, char *inbuf,  int stride,encodedata *ed){
 212         pixbuf pb;
 213         int i, row;
 214         pb.x = w;
 215         pb.y = h;
 216
 217         pb.pixels = inbuf;
 218         ed->count= 4;
 219         ed->nibblewaiting= 0;
 220
 221         row= 0;
 222         for( i= 0; i < pb.y; i++ ) {
 223                 encode_do_row(ed, &pb, row);
 224                 row+= 2;
 225                 if( row > pb.y ) {
 226                         row= 1;
 227                         ed->oddstart= ed->count;
 228                 }
 229         }
 230         encode_do_control(x,y, ed, &pb);
 231 }