PeerStreamer

/*

 * drawtext.c: print text over the screen

 ******************************************************************************

 * Options:

 * -f <filename>    font filename (MANDATORY!!!)

 * -s <pixel_size>  font size in pixels [default 16]

 * -b               print background

 * -o               outline glyphs (use the bg color)

 * -x <pos>         x position ( >= 0) [default 0]

 * -y <pos>         y position ( >= 0) [default 0]

 * -t <text>        text to print (will be passed to strftime())

 *                  MANDATORY: will be used even when -T is used.

 *                  in this case, -t will be used if some error

 *                  occurs

 * -T <filename>    file with the text (re-read every frame)

 * -c <#RRGGBB>     foreground color ('internet' way) [default #ffffff]

 * -C <#RRGGBB>     background color ('internet' way) [default #000000]

 *

 ******************************************************************************

 * Features:

 * - True Type, Type1 and others via FreeType2 library

 * - Font kerning (better output)

 * - Line Wrap (if the text doesn't fit, the next char go to the next line)

 * - Background box

 * - Outline

 ******************************************************************************

 * Author: Gustavo Sverzut Barbieri <gsbarbieri@yahoo.com.br>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#define MAXSIZE_TEXT 1024

#include "framehook.h"

#include <stdio.h>

#include <stdlib.h>

#include <fcntl.h>

#include <stdarg.h>

#include <string.h>

#include <unistd.h>

#undef time

#include <sys/time.h>

#include <time.h>

#include <ft2build.h>

#include FT_FREETYPE_H

#include FT_GLYPH_H

#define RGB_TO_YUV(rgb_color, yuv_color) { \

    yuv_color[0] = ( 0.257 * rgb_color[0]) + (0.504 * rgb_color[1]) + (0.098 * rgb_color[2]) +  16; \

    yuv_color[2] = ( 0.439 * rgb_color[0]) - (0.368 * rgb_color[1]) - (0.071 * rgb_color[2]) + 128; \

    yuv_color[1] = (-0.148 * rgb_color[0]) - (0.291 * rgb_color[1]) + (0.439 * rgb_color[2]) + 128; \

}

#define COPY_3(dst,src) { \

    dst[0]=src[0]; \

    dst[1]=src[1]; \

    dst[2]=src[2]; \

}

#define SET_PIXEL(picture, yuv_color, x, y) { \

    picture->data[0][ (x) + (y)*picture->linesize[0] ] = yuv_color[0]; \

    picture->data[1][ ((x/2) + (y/2)*picture->linesize[1]) ] = yuv_color[1]; \

    picture->data[2][ ((x/2) + (y/2)*picture->linesize[2]) ] = yuv_color[2]; \

}

#define GET_PIXEL(picture, yuv_color, x, y) { \

    yuv_color[0] = picture->data[0][ (x) + (y)*picture->linesize[0] ]; \

    yuv_color[1] = picture->data[1][ (x/2) + (y/2)*picture->linesize[1] ]; \

    yuv_color[2] = picture->data[2][ (x/2) + (y/2)*picture->linesize[2] ]; \

}

typedef struct {

  unsigned char *text;

  unsigned char *file;

  unsigned int x;

  unsigned int y;

  int bg;

  int outline;

  unsigned char bgcolor[3]; /* YUV */

  unsigned char fgcolor[3]; /* YUV */

  FT_Library library;

  FT_Face    face;

  FT_Glyph   glyphs[ 255 ];

  FT_Bitmap  bitmaps[ 255 ];

  int        advance[ 255 ];

  int        bitmap_left[ 255 ];

  int        bitmap_top[ 255 ];

  unsigned int glyphs_index[ 255 ];

  int        text_height;

  int        baseline;

  int use_kerning;

} ContextInfo;

void Release(void *ctx)

{

    if (ctx)

        av_free(ctx);

}

int ParseColor(char *text, unsigned char yuv_color[3])

{

  char tmp[3];

  unsigned char rgb_color[3];

  int i;

  tmp[2] = '\0';

  if ((!text) || (strlen(text) != 7) || (text[0] != '#') )

    return -1;

  for (i=0; i < 3; i++)

    {

      tmp[0] = text[i*2+1];

      tmp[1] = text[i*2+2];

      rgb_color[i] = strtol(tmp, NULL, 16);

    }

  RGB_TO_YUV(rgb_color, yuv_color);

  return 0;

}

int Configure(void **ctxp, int argc, char *argv[])

{

    int c;

    int error;

    ContextInfo *ci=NULL;

    char *font=NULL;

    unsigned int size=16;

    FT_BBox bbox;

    int yMax, yMin;

    *ctxp = av_mallocz(sizeof(ContextInfo));

    ci = (ContextInfo *) *ctxp;

    /* configure Context Info */

    ci->text = NULL;

    ci->file = NULL;

    ci->x = ci->y = 0;

    ci->fgcolor[0]=255;

    ci->fgcolor[1]=128;

    ci->fgcolor[2]=128;

    ci->bgcolor[0]=0;

    ci->fgcolor[1]=128;

    ci->fgcolor[2]=128;

    ci->bg = 0;

    ci->outline = 0;

    ci->text_height = 0;

    optind = 0;

    while ((c = getopt(argc, argv, "f:t:T:x:y:s:c:C:bo")) > 0) {

      switch (c) {

      case 'f':

        font = optarg;

        break;

      case 't':

        ci->text = av_strdup(optarg);

        break;

      case 'T':

        ci->file = av_strdup(optarg);

        break;

      case 'x':

        ci->x = (unsigned int) atoi(optarg);

        break;

      case 'y':

        ci->y = (unsigned int) atoi(optarg);

        break;

      case 's':

        size = (unsigned int) atoi(optarg);

        break;

      case 'c':

        if (ParseColor(optarg, ci->fgcolor) == -1)

          {

            fprintf(stderr, "ERROR: Invalid foreground color: '%s'. You must specify the color in the internet way(packaged hex): #RRGGBB, ie: -c #ffffff (for white foreground)\n",optarg);

            return -1;

          }

        break;

      case 'C':

        if (ParseColor(optarg, ci->bgcolor) == -1)

          {

            fprintf(stderr, "ERROR: Invalid foreground color: '%s'. You must specify the color in the internet way(packaged hex): #RRGGBB, ie: -c #ffffff (for white foreground)\n",optarg);

            return -1;

          }

        break;

      case 'b':

        ci->bg=1;

        break;

      case 'o':

        ci->outline=1;

        break;

      case '?':

        fprintf(stderr, "ERROR: Unrecognized argument '%s'\n", argv[optind]);

        return -1;

      }

    }

    if (!ci->text)

      {

        fprintf(stderr,"ERROR: No text provided (-t text)\n");

        return -1;

      }

    if (ci->file)

      {

        FILE *fp;

        if ((fp=fopen(ci->file, "r")) == NULL)

          {

            perror("WARNING: the file could not be opened. Using text provided with -t switch. ");

          }

        else

          {

            fclose(fp);

          }

      }

    if (!font)

      {

        fprintf(stderr,"ERROR: No font file provided! (-f filename)\n");

        return -1;

      }

    if ((error = FT_Init_FreeType(&(ci->library))) != 0)

      {

        fprintf(stderr,"ERROR: Could not load FreeType (error# %d)\n",error);

        return -1;

      }

    if ((error = FT_New_Face( ci->library, font, 0, &(ci->face) )) != 0)

      {

        fprintf(stderr,"ERROR: Could not load face: %s  (error# %d)\n",font, error);

        return -1;

      }

    if ((error = FT_Set_Pixel_Sizes( ci->face, 0, size)) != 0)

      {

        fprintf(stderr,"ERROR: Could not set font size to %d pixels (error# %d)\n",size, error);

        return -1;

      }

    ci->use_kerning = FT_HAS_KERNING(ci->face);

    /* load and cache glyphs */

    yMax = -32000;

    yMin =  32000;

    for (c=0; c < 256; c++)

      {

        /* Load char */

        error = FT_Load_Char( ci->face, (unsigned char) c, FT_LOAD_RENDER | FT_LOAD_MONOCHROME );

        if (error) continue;  /* ignore errors */

        /* Save bitmap */

        ci->bitmaps[c] = ci->face->glyph->bitmap;

        /* Save bitmap left */

        ci->bitmap_left[c] = ci->face->glyph->bitmap_left;

        /* Save bitmap top */

        ci->bitmap_top[c] = ci->face->glyph->bitmap_top;

        /* Save advance */

        ci->advance[c] = ci->face->glyph->advance.x >> 6;

        /* Save glyph */

        error = FT_Get_Glyph( ci->face->glyph, &(ci->glyphs[c]) );

        /* Save glyph index */

        ci->glyphs_index[c] = FT_Get_Char_Index( ci->face, (unsigned char) c );

        /* Measure text height to calculate text_height (or the maximum text height) */

        FT_Glyph_Get_CBox( ci->glyphs[ c ], ft_glyph_bbox_pixels, &bbox );

        if (bbox.yMax > yMax)

          yMax = bbox.yMax;

        if (bbox.yMin < yMin)

          yMin = bbox.yMin;

      }

    ci->text_height = yMax - yMin;

    ci->baseline = yMax;

    return 0;

}

inline void draw_glyph(AVPicture *picture, FT_Bitmap *bitmap, unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned char yuv_fgcolor[3], unsigned char yuv_bgcolor[3], int outline)

{

  int r, c;

  int spixel, dpixel[3], in_glyph=0;

  if (bitmap->pixel_mode == ft_pixel_mode_mono)

    {

      in_glyph = 0;

      for (r=0; (r < bitmap->rows) && (r+y < height); r++)

        {

          for (c=0; (c < bitmap->width) && (c+x < width); c++)

            {

              /* pixel in the picture (destination) */

              GET_PIXEL(picture, dpixel, (c+x), (y+r));

              /* pixel in the glyph bitmap (source) */

              spixel = bitmap->buffer[r*bitmap->pitch +c/8] & (0x80>>(c%8));

              if (spixel)

                COPY_3(dpixel, yuv_fgcolor);

              if (outline)

                {

                  /* border detection: */

                  if ( (!in_glyph) && (spixel) )

                    /* left border detected */

                    {

                      in_glyph = 1;

                      /* draw left pixel border */

                      if (c-1 >= 0)

                        SET_PIXEL(picture, yuv_bgcolor, (c+x-1), (y+r));

                    }

                  else if ( (in_glyph) && (!spixel) )

                    /* right border detected */

                    {

                      in_glyph = 0;

                      /* 'draw' right pixel border */

                      COPY_3(dpixel, yuv_bgcolor);

                    }

                  if (in_glyph)

                    /* see if we have a top/bottom border */

                    {

                      /* top */

                      if ( (r-1 >= 0) && (! bitmap->buffer[(r-1)*bitmap->pitch +c/8] & (0x80>>(c%8))) )

                        /* we have a top border */

                        SET_PIXEL(picture, yuv_bgcolor, (c+x), (y+r-1));

                      /* bottom */

                      if ( (r+1 < height) && (! bitmap->buffer[(r+1)*bitmap->pitch +c/8] & (0x80>>(c%8))) )

                        /* we have a bottom border */

                        SET_PIXEL(picture, yuv_bgcolor, (c+x), (y+r+1));

                    }

                }

              SET_PIXEL(picture, dpixel, (c+x), (y+r));

            }

        }

    }

}

inline void draw_box(AVPicture *picture, unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned char yuv_color[3])

{

  int i, j;

  for (j = 0; (j < height); j++)

    for (i = 0; (i < width); i++)

      {

        SET_PIXEL(picture, yuv_color, (i+x), (y+j));

      }

}

void Process(void *ctx, AVPicture *picture, enum PixelFormat pix_fmt, int width, int height, int64_t pts)

{

  ContextInfo *ci = (ContextInfo *) ctx;

  FT_Face face = ci->face;

  FT_GlyphSlot  slot = face->glyph;

  unsigned char *text = ci->text;

  unsigned char c;

  int x = 0, y = 0, i=0, size=0;

  unsigned char buff[MAXSIZE_TEXT];

  unsigned char tbuff[MAXSIZE_TEXT];

  time_t now = time(0);

  int str_w, str_w_max;

  FT_Vector pos[MAXSIZE_TEXT];

  FT_Vector delta;

  if (ci->file)

    {

      int fd = open(ci->file, O_RDONLY);

      if (fd < 0)

        {

          text = ci->text;

          perror("WARNING: the file could not be opened. Using text provided with -t switch. ");

        }

      else

        {

          int l = read(fd, tbuff, sizeof(tbuff) - 1);

          if (l >= 0)

            {

              tbuff[l] = 0;

              text = tbuff;

            }

          else

            {

              text = ci->text;

              perror("WARNING: the file could not be opened. Using text provided with -t switch. ");

            }

          close(fd);

        }

    }

  else

    {

      text = ci->text;

    }

  strftime(buff, sizeof(buff), text, localtime(&now));

  text = buff;

  size = strlen(text);

  /* measure string size and save glyphs position*/

  str_w = str_w_max = 0;

  x = ci->x;

  y = ci->y;

  for (i=0; i < size; i++)

    {

      c = text[i];

      /* kerning */

      if ( (ci->use_kerning) && (i > 0) && (ci->glyphs_index[c]) )

        {

          FT_Get_Kerning( ci->face,

                          ci->glyphs_index[ text[i-1] ],

                          ci->glyphs_index[c],

                          ft_kerning_default,

                          &delta );

          x += delta.x >> 6;

        }

      if (( (x + ci->advance[ c ]) >= width ) || ( c == '\n' ))

        {

          str_w = width - ci->x - 1;

          y += ci->text_height;

          x = ci->x;

        }

      /* save position */

      pos[i].x = x + ci->bitmap_left[c];

      pos[i].y = y - ci->bitmap_top[c] + ci->baseline;

      x += ci->advance[c];

      if (str_w > str_w_max)

        str_w_max = str_w;

    }

  if (ci->bg)

    {

      /* Check if it doesn't pass the limits */

      if ( str_w_max + ci->x >= width )

        str_w_max = width - ci->x - 1;

      if ( y >= height )

        y = height - 1 - 2*ci->y;

      /* Draw Background */

      draw_box( picture, ci->x, ci->y, str_w_max, y - ci->y, ci->bgcolor );

    }

  /* Draw Glyphs */

  for (i=0; i < size; i++)

    {

      c = text[i];

      if (

          ( (c == '_') && (text == ci->text) ) || /* skip '_' (consider as space)

                                                     IF text was specified in cmd line

                                                     (which doesn't like neasted quotes)  */

          ( c == '\n' ) /* Skip new line char, just go to new line */

          )

        continue;

        /* now, draw to our target surface */

        draw_glyph( picture,

                    &(ci->bitmaps[ c ]),

                    pos[i].x,

                    pos[i].y,

                    width,

                    height,

                    ci->fgcolor,

                    ci->bgcolor,

                    ci->outline );

      /* increment pen position */

      x += slot->advance.x >> 6;

    }

}