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libavfilter/vf_drawtext.c

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00001 /*
00002  * Copyright (c) 2011 Stefano Sabatini
00003  * Copyright (c) 2010 S.N. Hemanth Meenakshisundaram
00004  * Copyright (c) 2003 Gustavo Sverzut Barbieri <gsbarbieri@yahoo.com.br>
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00029 #include <sys/time.h>
00030 #include <time.h>
00031 
00032 #include "libavutil/colorspace.h"
00033 #include "libavutil/file.h"
00034 #include "libavutil/opt.h"
00035 #include "libavutil/parseutils.h"
00036 #include "libavutil/pixdesc.h"
00037 #include "libavutil/tree.h"
00038 #include "avfilter.h"
00039 #include "drawutils.h"
00040 
00041 #undef time
00042 
00043 #include <ft2build.h>
00044 #include <freetype/config/ftheader.h>
00045 #include FT_FREETYPE_H
00046 #include FT_GLYPH_H
00047 
00048 typedef struct {
00049     const AVClass *class;
00050     uint8_t *fontfile;              
00051     uint8_t *text;                  
00052     uint8_t *expanded_text;         
00053     size_t   expanded_text_size;    
00054     int ft_load_flags;              
00055     FT_Vector *positions;           
00056     size_t nb_positions;            
00057     char *textfile;                 
00058     unsigned int x;                 
00059     unsigned int y;                 
00060     int shadowx, shadowy;
00061     unsigned int fontsize;          
00062     char *fontcolor_string;         
00063     char *boxcolor_string;          
00064     char *shadowcolor_string;       
00065     uint8_t fontcolor[4];           
00066     uint8_t boxcolor[4];            
00067     uint8_t shadowcolor[4];         
00068     uint8_t fontcolor_rgba[4];      
00069     uint8_t boxcolor_rgba[4];       
00070     uint8_t shadowcolor_rgba[4];    
00071 
00072     short int draw_box;             
00073     int use_kerning;                
00074     int tabsize;                    
00075 
00076     FT_Library library;             
00077     FT_Face face;                   
00078     struct AVTreeNode *glyphs;      
00079     int hsub, vsub;                 
00080     int is_packed_rgb;
00081     int pixel_step[4];              
00082     uint8_t rgba_map[4];            
00083     uint8_t *box_line[4];           
00084 } DrawTextContext;
00085 
00086 #define OFFSET(x) offsetof(DrawTextContext, x)
00087 
00088 static const AVOption drawtext_options[]= {
00089 {"fontfile", "set font file",        OFFSET(fontfile),           FF_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX },
00090 {"text",     "set text",             OFFSET(text),               FF_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX },
00091 {"textfile", "set text file",        OFFSET(textfile),           FF_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX },
00092 {"fontcolor","set foreground color", OFFSET(fontcolor_string),   FF_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX },
00093 {"boxcolor", "set box color",        OFFSET(boxcolor_string),    FF_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX },
00094 {"shadowcolor", "set shadow color",  OFFSET(shadowcolor_string), FF_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX },
00095 {"box",      "set box",              OFFSET(draw_box),           FF_OPT_TYPE_INT,    {.dbl=0},     0,        1        },
00096 {"fontsize", "set font size",        OFFSET(fontsize),           FF_OPT_TYPE_INT,    {.dbl=16},    1,        72       },
00097 {"x",        "set x",                OFFSET(x),                  FF_OPT_TYPE_INT,    {.dbl=0},     0,        INT_MAX  },
00098 {"y",        "set y",                OFFSET(y),                  FF_OPT_TYPE_INT,    {.dbl=0},     0,        INT_MAX  },
00099 {"shadowx",  "set x",                OFFSET(shadowx),            FF_OPT_TYPE_INT,    {.dbl=0},     INT_MIN,  INT_MAX  },
00100 {"shadowy",  "set y",                OFFSET(shadowy),            FF_OPT_TYPE_INT,    {.dbl=0},     INT_MIN,  INT_MAX  },
00101 {"tabsize",  "set tab size",         OFFSET(tabsize),            FF_OPT_TYPE_INT,    {.dbl=4},     0,        INT_MAX  },
00102 
00103 /* FT_LOAD_* flags */
00104 {"ft_load_flags", "set font loading flags for libfreetype",   OFFSET(ft_load_flags),  FF_OPT_TYPE_FLAGS,  {.dbl=FT_LOAD_DEFAULT|FT_LOAD_RENDER}, 0, INT_MAX, 0, "ft_load_flags" },
00105 {"default",                     "set default",                     0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_DEFAULT},                     INT_MIN, INT_MAX, 0, "ft_load_flags" },
00106 {"no_scale",                    "set no_scale",                    0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_SCALE},                    INT_MIN, INT_MAX, 0, "ft_load_flags" },
00107 {"no_hinting",                  "set no_hinting",                  0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_HINTING},                  INT_MIN, INT_MAX, 0, "ft_load_flags" },
00108 {"render",                      "set render",                      0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_RENDER},                      INT_MIN, INT_MAX, 0, "ft_load_flags" },
00109 {"no_bitmap",                   "set no_bitmap",                   0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_BITMAP},                   INT_MIN, INT_MAX, 0, "ft_load_flags" },
00110 {"vertical_layout",             "set vertical_layout",             0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_VERTICAL_LAYOUT},             INT_MIN, INT_MAX, 0, "ft_load_flags" },
00111 {"force_autohint",              "set force_autohint",              0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_FORCE_AUTOHINT},              INT_MIN, INT_MAX, 0, "ft_load_flags" },
00112 {"crop_bitmap",                 "set crop_bitmap",                 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_CROP_BITMAP},                 INT_MIN, INT_MAX, 0, "ft_load_flags" },
00113 {"pedantic",                    "set pedantic",                    0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_PEDANTIC},                    INT_MIN, INT_MAX, 0, "ft_load_flags" },
00114 {"ignore_global_advance_width", "set ignore_global_advance_width", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
00115 {"no_recurse",                  "set no_recurse",                  0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_RECURSE},                  INT_MIN, INT_MAX, 0, "ft_load_flags" },
00116 {"ignore_transform",            "set ignore_transform",            0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_TRANSFORM},            INT_MIN, INT_MAX, 0, "ft_load_flags" },
00117 {"monochrome",                  "set monochrome",                  0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_MONOCHROME},                  INT_MIN, INT_MAX, 0, "ft_load_flags" },
00118 {"linear_design",               "set linear_design",               0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_LINEAR_DESIGN},               INT_MIN, INT_MAX, 0, "ft_load_flags" },
00119 {"no_autohint",                 "set no_autohint",                 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_AUTOHINT},                 INT_MIN, INT_MAX, 0, "ft_load_flags" },
00120 {NULL},
00121 };
00122 
00123 static const char *drawtext_get_name(void *ctx)
00124 {
00125     return "drawtext";
00126 }
00127 
00128 static const AVClass drawtext_class = {
00129     "DrawTextContext",
00130     drawtext_get_name,
00131     drawtext_options
00132 };
00133 
00134 #undef __FTERRORS_H__
00135 #define FT_ERROR_START_LIST {
00136 #define FT_ERRORDEF(e, v, s) { (e), (s) },
00137 #define FT_ERROR_END_LIST { 0, NULL } };
00138 
00139 struct ft_error
00140 {
00141     int err;
00142     const char *err_msg;
00143 } static ft_errors[] =
00144 #include FT_ERRORS_H
00145 
00146 #define FT_ERRMSG(e) ft_errors[e].err_msg
00147 
00148 typedef struct {
00149     FT_Glyph *glyph;
00150     uint32_t code;
00151     FT_Bitmap bitmap; 
00152     FT_BBox bbox;
00153     int advance;
00154     int bitmap_left;
00155     int bitmap_top;
00156 } Glyph;
00157 
00158 static int glyph_cmp(void *key, const void *b)
00159 {
00160     const Glyph *a = key, *bb = b;
00161     int64_t diff = (int64_t)a->code - (int64_t)bb->code;
00162     return diff > 0 ? 1 : diff < 0 ? -1 : 0;
00163 }
00164 
00168 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
00169 {
00170     DrawTextContext *dtext = ctx->priv;
00171     Glyph *glyph;
00172     struct AVTreeNode *node = NULL;
00173     int ret;
00174 
00175     /* load glyph into dtext->face->glyph */
00176     if (FT_Load_Char(dtext->face, code, dtext->ft_load_flags))
00177         return AVERROR(EINVAL);
00178 
00179     /* save glyph */
00180     if (!(glyph = av_mallocz(sizeof(*glyph))) ||
00181         !(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
00182         ret = AVERROR(ENOMEM);
00183         goto error;
00184     }
00185     glyph->code  = code;
00186 
00187     if (FT_Get_Glyph(dtext->face->glyph, glyph->glyph)) {
00188         ret = AVERROR(EINVAL);
00189         goto error;
00190     }
00191 
00192     glyph->bitmap      = dtext->face->glyph->bitmap;
00193     glyph->bitmap_left = dtext->face->glyph->bitmap_left;
00194     glyph->bitmap_top  = dtext->face->glyph->bitmap_top;
00195     glyph->advance     = dtext->face->glyph->advance.x >> 6;
00196 
00197     /* measure text height to calculate text_height (or the maximum text height) */
00198     FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
00199 
00200     /* cache the newly created glyph */
00201     if (!(node = av_mallocz(av_tree_node_size))) {
00202         ret = AVERROR(ENOMEM);
00203         goto error;
00204     }
00205     av_tree_insert(&dtext->glyphs, glyph, glyph_cmp, &node);
00206 
00207     if (glyph_ptr)
00208         *glyph_ptr = glyph;
00209     return 0;
00210 
00211 error:
00212     if (glyph)
00213         av_freep(&glyph->glyph);
00214     av_freep(&glyph);
00215     av_freep(&node);
00216     return ret;
00217 }
00218 
00219 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00220 {
00221     int err;
00222     DrawTextContext *dtext = ctx->priv;
00223     Glyph *glyph;
00224 
00225     dtext->class = &drawtext_class;
00226     av_opt_set_defaults2(dtext, 0, 0);
00227     dtext->fontcolor_string = av_strdup("black");
00228     dtext->boxcolor_string = av_strdup("white");
00229     dtext->shadowcolor_string = av_strdup("black");
00230 
00231     if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
00232         av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
00233         return err;
00234     }
00235 
00236     if (!dtext->fontfile) {
00237         av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
00238         return AVERROR(EINVAL);
00239     }
00240 
00241     if (dtext->textfile) {
00242         uint8_t *textbuf;
00243         size_t textbuf_size;
00244 
00245         if (dtext->text) {
00246             av_log(ctx, AV_LOG_ERROR,
00247                    "Both text and text file provided. Please provide only one\n");
00248             return AVERROR(EINVAL);
00249         }
00250         if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
00251             av_log(ctx, AV_LOG_ERROR,
00252                    "The text file '%s' could not be read or is empty\n",
00253                    dtext->textfile);
00254             return err;
00255         }
00256 
00257         if (!(dtext->text = av_malloc(textbuf_size+1)))
00258             return AVERROR(ENOMEM);
00259         memcpy(dtext->text, textbuf, textbuf_size);
00260         dtext->text[textbuf_size] = 0;
00261         av_file_unmap(textbuf, textbuf_size);
00262     }
00263 
00264     if (!dtext->text) {
00265         av_log(ctx, AV_LOG_ERROR,
00266                "Either text or a valid file must be provided\n");
00267         return AVERROR(EINVAL);
00268     }
00269 
00270     if ((err = av_parse_color(dtext->fontcolor_rgba, dtext->fontcolor_string, -1, ctx))) {
00271         av_log(ctx, AV_LOG_ERROR,
00272                "Invalid font color '%s'\n", dtext->fontcolor_string);
00273         return err;
00274     }
00275 
00276     if ((err = av_parse_color(dtext->boxcolor_rgba, dtext->boxcolor_string, -1, ctx))) {
00277         av_log(ctx, AV_LOG_ERROR,
00278                "Invalid box color '%s'\n", dtext->boxcolor_string);
00279         return err;
00280     }
00281 
00282     if ((err = av_parse_color(dtext->shadowcolor_rgba, dtext->shadowcolor_string, -1, ctx))) {
00283         av_log(ctx, AV_LOG_ERROR,
00284                "Invalid shadow color '%s'\n", dtext->shadowcolor_string);
00285         return err;
00286     }
00287 
00288     if ((err = FT_Init_FreeType(&(dtext->library)))) {
00289         av_log(ctx, AV_LOG_ERROR,
00290                "Could not load FreeType: %s\n", FT_ERRMSG(err));
00291         return AVERROR(EINVAL);
00292     }
00293 
00294     /* load the face, and set up the encoding, which is by default UTF-8 */
00295     if ((err = FT_New_Face(dtext->library, dtext->fontfile, 0, &dtext->face))) {
00296         av_log(ctx, AV_LOG_ERROR, "Could not load fontface from file '%s': %s\n",
00297                dtext->fontfile, FT_ERRMSG(err));
00298         return AVERROR(EINVAL);
00299     }
00300     if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
00301         av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
00302                dtext->fontsize, FT_ERRMSG(err));
00303         return AVERROR(EINVAL);
00304     }
00305 
00306     dtext->use_kerning = FT_HAS_KERNING(dtext->face);
00307 
00308     /* load the fallback glyph with code 0 */
00309     load_glyph(ctx, NULL, 0);
00310 
00311     /* set the tabsize in pixels */
00312     if ((err = load_glyph(ctx, &glyph, ' ') < 0)) {
00313         av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
00314         return err;
00315     }
00316     dtext->tabsize *= glyph->advance;
00317 
00318 #if !HAVE_LOCALTIME_R
00319     av_log(ctx, AV_LOG_WARNING, "strftime() expansion unavailable!\n");
00320 #endif
00321 
00322     return 0;
00323 }
00324 
00325 static int query_formats(AVFilterContext *ctx)
00326 {
00327     static const enum PixelFormat pix_fmts[] = {
00328         PIX_FMT_ARGB,    PIX_FMT_RGBA,
00329         PIX_FMT_ABGR,    PIX_FMT_BGRA,
00330         PIX_FMT_RGB24,   PIX_FMT_BGR24,
00331         PIX_FMT_YUV420P, PIX_FMT_YUV444P,
00332         PIX_FMT_YUV422P, PIX_FMT_YUV411P,
00333         PIX_FMT_YUV410P, PIX_FMT_YUV440P,
00334         PIX_FMT_NONE
00335     };
00336 
00337     avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
00338     return 0;
00339 }
00340 
00341 static int glyph_enu_free(void *opaque, void *elem)
00342 {
00343     av_free(elem);
00344     return 0;
00345 }
00346 
00347 static av_cold void uninit(AVFilterContext *ctx)
00348 {
00349     DrawTextContext *dtext = ctx->priv;
00350     int i;
00351 
00352     av_freep(&dtext->fontfile);
00353     av_freep(&dtext->text);
00354     av_freep(&dtext->expanded_text);
00355     av_freep(&dtext->fontcolor_string);
00356     av_freep(&dtext->boxcolor_string);
00357     av_freep(&dtext->positions);
00358     av_freep(&dtext->shadowcolor_string);
00359     av_tree_enumerate(dtext->glyphs, NULL, NULL, glyph_enu_free);
00360     av_tree_destroy(dtext->glyphs);
00361     dtext->glyphs = 0;
00362     FT_Done_Face(dtext->face);
00363     FT_Done_FreeType(dtext->library);
00364 
00365     for (i = 0; i < 4; i++) {
00366         av_freep(&dtext->box_line[i]);
00367         dtext->pixel_step[i] = 0;
00368     }
00369 
00370 }
00371 
00372 static int config_input(AVFilterLink *inlink)
00373 {
00374     DrawTextContext *dtext = inlink->dst->priv;
00375     const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
00376     int ret;
00377 
00378     dtext->hsub = pix_desc->log2_chroma_w;
00379     dtext->vsub = pix_desc->log2_chroma_h;
00380 
00381     if ((ret =
00382          ff_fill_line_with_color(dtext->box_line, dtext->pixel_step,
00383                                  inlink->w, dtext->boxcolor,
00384                                  inlink->format, dtext->boxcolor_rgba,
00385                                  &dtext->is_packed_rgb, dtext->rgba_map)) < 0)
00386         return ret;
00387 
00388     if (!dtext->is_packed_rgb) {
00389         uint8_t *rgba = dtext->fontcolor_rgba;
00390         dtext->fontcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
00391         dtext->fontcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
00392         dtext->fontcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
00393         dtext->fontcolor[3] = rgba[3];
00394         rgba = dtext->shadowcolor_rgba;
00395         dtext->shadowcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
00396         dtext->shadowcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
00397         dtext->shadowcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
00398         dtext->shadowcolor[3] = rgba[3];
00399     }
00400 
00401     return 0;
00402 }
00403 
00404 #define GET_BITMAP_VAL(r, c)                                            \
00405     bitmap->pixel_mode == FT_PIXEL_MODE_MONO ?                          \
00406         (bitmap->buffer[(r) * bitmap->pitch + ((c)>>3)] & (0x80 >> ((c)&7))) * 255 : \
00407          bitmap->buffer[(r) * bitmap->pitch +  (c)]
00408 
00409 #define SET_PIXEL_YUV(picref, yuva_color, val, x, y, hsub, vsub) {           \
00410     luma_pos    = ((x)          ) + ((y)          ) * picref->linesize[0]; \
00411     alpha = yuva_color[3] * (val) * 129;                               \
00412     picref->data[0][luma_pos]    = (alpha * yuva_color[0] + (255*255*129 - alpha) * picref->data[0][luma_pos]   ) >> 23; \
00413     if (((x) & ((1<<(hsub)) - 1)) == 0 && ((y) & ((1<<(vsub)) - 1)) == 0) {\
00414         chroma_pos1 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[1]; \
00415         chroma_pos2 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[2]; \
00416         picref->data[1][chroma_pos1] = (alpha * yuva_color[1] + (255*255*129 - alpha) * picref->data[1][chroma_pos1]) >> 23; \
00417         picref->data[2][chroma_pos2] = (alpha * yuva_color[2] + (255*255*129 - alpha) * picref->data[2][chroma_pos2]) >> 23; \
00418     }\
00419 }
00420 
00421 static inline int draw_glyph_yuv(AVFilterBufferRef *picref, FT_Bitmap *bitmap, unsigned int x,
00422                                  unsigned int y, unsigned int width, unsigned int height,
00423                                  const uint8_t yuva_color[4], int hsub, int vsub)
00424 {
00425     int r, c, alpha;
00426     unsigned int luma_pos, chroma_pos1, chroma_pos2;
00427     uint8_t src_val, dst_pixel[4];
00428 
00429     for (r = 0; r < bitmap->rows && r+y < height; r++) {
00430         for (c = 0; c < bitmap->width && c+x < width; c++) {
00431             /* get pixel in the picref (destination) */
00432             dst_pixel[0] = picref->data[0][  c+x           +  (y+r)          * picref->linesize[0]];
00433             dst_pixel[1] = picref->data[1][((c+x) >> hsub) + ((y+r) >> vsub) * picref->linesize[1]];
00434             dst_pixel[2] = picref->data[2][((c+x) >> hsub) + ((y+r) >> vsub) * picref->linesize[2]];
00435 
00436             /* get intensity value in the glyph bitmap (source) */
00437             src_val = GET_BITMAP_VAL(r, c);
00438             if (!src_val)
00439                 continue;
00440 
00441             SET_PIXEL_YUV(picref, yuva_color, src_val, c+x, y+r, hsub, vsub);
00442         }
00443     }
00444 
00445     return 0;
00446 }
00447 
00448 #define SET_PIXEL_RGB(picref, rgba_color, val, x, y, pixel_step, r_off, g_off, b_off, a_off) { \
00449     p   = picref->data[0] + (x) * pixel_step + ((y) * picref->linesize[0]); \
00450     alpha = rgba_color[3] * (val) * 129;                              \
00451     *(p+r_off) = (alpha * rgba_color[0] + (255*255*129 - alpha) * *(p+r_off)) >> 23; \
00452     *(p+g_off) = (alpha * rgba_color[1] + (255*255*129 - alpha) * *(p+g_off)) >> 23; \
00453     *(p+b_off) = (alpha * rgba_color[2] + (255*255*129 - alpha) * *(p+b_off)) >> 23; \
00454 }
00455 
00456 static inline int draw_glyph_rgb(AVFilterBufferRef *picref, FT_Bitmap *bitmap,
00457                                  unsigned int x, unsigned int y,
00458                                  unsigned int width, unsigned int height, int pixel_step,
00459                                  const uint8_t rgba_color[4], const uint8_t rgba_map[4])
00460 {
00461     int r, c, alpha;
00462     uint8_t *p;
00463     uint8_t src_val, dst_pixel[4];
00464 
00465     for (r = 0; r < bitmap->rows && r+y < height; r++) {
00466         for (c = 0; c < bitmap->width && c+x < width; c++) {
00467             /* get pixel in the picref (destination) */
00468             dst_pixel[0] = picref->data[0][(c+x + rgba_map[0]) * pixel_step +
00469                                            (y+r) * picref->linesize[0]];
00470             dst_pixel[1] = picref->data[0][(c+x + rgba_map[1]) * pixel_step +
00471                                            (y+r) * picref->linesize[0]];
00472             dst_pixel[2] = picref->data[0][(c+x + rgba_map[2]) * pixel_step +
00473                                            (y+r) * picref->linesize[0]];
00474 
00475             /* get intensity value in the glyph bitmap (source) */
00476             src_val = GET_BITMAP_VAL(r, c);
00477             if (!src_val)
00478                 continue;
00479 
00480             SET_PIXEL_RGB(picref, rgba_color, src_val, c+x, y+r, pixel_step,
00481                           rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
00482         }
00483     }
00484 
00485     return 0;
00486 }
00487 
00488 static inline void drawbox(AVFilterBufferRef *picref, unsigned int x, unsigned int y,
00489                            unsigned int width, unsigned int height,
00490                            uint8_t *line[4], int pixel_step[4], uint8_t color[4],
00491                            int hsub, int vsub, int is_rgba_packed, uint8_t rgba_map[4])
00492 {
00493     int i, j, alpha;
00494 
00495     if (color[3] != 0xFF) {
00496         if (is_rgba_packed) {
00497             uint8_t *p;
00498             for (j = 0; j < height; j++)
00499                 for (i = 0; i < width; i++)
00500                     SET_PIXEL_RGB(picref, color, 255, i+x, y+j, pixel_step[0],
00501                                   rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
00502         } else {
00503             unsigned int luma_pos, chroma_pos1, chroma_pos2;
00504             for (j = 0; j < height; j++)
00505                 for (i = 0; i < width; i++)
00506                     SET_PIXEL_YUV(picref, color, 255, i+x, y+j, hsub, vsub);
00507         }
00508     } else {
00509         ff_draw_rectangle(picref->data, picref->linesize,
00510                           line, pixel_step, hsub, vsub,
00511                           x, y, width, height);
00512     }
00513 }
00514 
00515 static inline int is_newline(uint32_t c)
00516 {
00517     return (c == '\n' || c == '\r' || c == '\f' || c == '\v');
00518 }
00519 
00520 static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
00521                        int width, int height, const uint8_t rgbcolor[4], const uint8_t yuvcolor[4], int x, int y)
00522 {
00523     char *text = HAVE_LOCALTIME_R ? dtext->expanded_text : dtext->text;
00524     uint32_t code = 0;
00525     int i;
00526     uint8_t *p;
00527     Glyph *glyph = NULL;
00528 
00529     for (i = 0, p = text; *p; i++) {
00530         Glyph dummy = { 0 };
00531         GET_UTF8(code, *p++, continue;);
00532 
00533         /* skip new line chars, just go to new line */
00534         if (code == '\n' || code == '\r' || code == '\t')
00535             continue;
00536 
00537         dummy.code = code;
00538         glyph = av_tree_find(dtext->glyphs, &dummy, (void *)glyph_cmp, NULL);
00539 
00540         if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
00541             glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
00542             return AVERROR(EINVAL);
00543 
00544         if (dtext->is_packed_rgb) {
00545             draw_glyph_rgb(picref, &glyph->bitmap,
00546                            dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
00547                            dtext->pixel_step[0], rgbcolor, dtext->rgba_map);
00548         } else {
00549             draw_glyph_yuv(picref, &glyph->bitmap,
00550                            dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
00551                            yuvcolor, dtext->hsub, dtext->vsub);
00552         }
00553     }
00554 
00555     return 0;
00556 }
00557 
00558 static int draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref,
00559                      int width, int height)
00560 {
00561     DrawTextContext *dtext = ctx->priv;
00562     uint32_t code = 0, prev_code = 0;
00563     int x = 0, y = 0, i = 0, ret;
00564     int text_height, baseline;
00565     char *text = dtext->text;
00566     uint8_t *p;
00567     int str_w = 0, len;
00568     int y_min = 32000, y_max = -32000;
00569     FT_Vector delta;
00570     Glyph *glyph = NULL, *prev_glyph = NULL;
00571     Glyph dummy = { 0 };
00572 
00573 #if HAVE_LOCALTIME_R
00574     time_t now = time(0);
00575     struct tm ltime;
00576     uint8_t *buf = dtext->expanded_text;
00577     int buf_size = dtext->expanded_text_size;
00578 
00579     if (!buf) {
00580         buf_size = 2*strlen(dtext->text)+1;
00581         buf = av_malloc(buf_size);
00582     }
00583 
00584     localtime_r(&now, &ltime);
00585 
00586     do {
00587         *buf = 1;
00588         if (strftime(buf, buf_size, dtext->text, &ltime) != 0 || *buf == 0)
00589             break;
00590         buf_size *= 2;
00591     } while ((buf = av_realloc(buf, buf_size)));
00592 
00593     if (!buf)
00594         return AVERROR(ENOMEM);
00595     text = dtext->expanded_text = buf;
00596     dtext->expanded_text_size = buf_size;
00597 #endif
00598     if ((len = strlen(text)) > dtext->nb_positions) {
00599         if (!(dtext->positions =
00600               av_realloc(dtext->positions, len*sizeof(*dtext->positions))))
00601             return AVERROR(ENOMEM);
00602         dtext->nb_positions = len;
00603     }
00604 
00605     x = dtext->x;
00606     y = dtext->y;
00607 
00608     /* load and cache glyphs */
00609     for (i = 0, p = text; *p; i++) {
00610         GET_UTF8(code, *p++, continue;);
00611 
00612         /* get glyph */
00613         dummy.code = code;
00614         glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
00615         if (!glyph)
00616             load_glyph(ctx, &glyph, code);
00617 
00618         y_min = FFMIN(glyph->bbox.yMin, y_min);
00619         y_max = FFMAX(glyph->bbox.yMax, y_max);
00620     }
00621     text_height = y_max - y_min;
00622     baseline    = y_max;
00623 
00624     /* compute and save position for each glyph */
00625     glyph = NULL;
00626     for (i = 0, p = text; *p; i++) {
00627         GET_UTF8(code, *p++, continue;);
00628 
00629         /* skip the \n in the sequence \r\n */
00630         if (prev_code == '\r' && code == '\n')
00631             continue;
00632 
00633         prev_code = code;
00634         if (is_newline(code)) {
00635             str_w = FFMAX(str_w, x - dtext->x);
00636             y += text_height;
00637             x = dtext->x;
00638             continue;
00639         }
00640 
00641         /* get glyph */
00642         prev_glyph = glyph;
00643         dummy.code = code;
00644         glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
00645 
00646         /* kerning */
00647         if (dtext->use_kerning && prev_glyph && glyph->code) {
00648             FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
00649                            ft_kerning_default, &delta);
00650             x += delta.x >> 6;
00651         }
00652 
00653         if (x + glyph->bbox.xMax >= width) {
00654             str_w = FFMAX(str_w, x - dtext->x);
00655             y += text_height;
00656             x = dtext->x;
00657         }
00658 
00659         /* save position */
00660         dtext->positions[i].x = x + glyph->bitmap_left;
00661         dtext->positions[i].y = y - glyph->bitmap_top + baseline;
00662         if (code == '\t') x  = (x / dtext->tabsize + 1)*dtext->tabsize;
00663         else              x += glyph->advance;
00664     }
00665 
00666     str_w = FFMIN(width - dtext->x - 1, FFMAX(str_w, x - dtext->x));
00667     y     = FFMIN(y + text_height, height - 1);
00668 
00669     /* draw box */
00670     if (dtext->draw_box)
00671         drawbox(picref, dtext->x, dtext->y, str_w, y-dtext->y,
00672                 dtext->box_line, dtext->pixel_step, dtext->boxcolor,
00673                 dtext->hsub, dtext->vsub, dtext->is_packed_rgb, dtext->rgba_map);
00674 
00675     if (dtext->shadowx || dtext->shadowy) {
00676         if ((ret = draw_glyphs(dtext, picref, width, height, dtext->shadowcolor_rgba,
00677                                dtext->shadowcolor, dtext->shadowx, dtext->shadowy)) < 0)
00678             return ret;
00679     }
00680 
00681     if ((ret = draw_glyphs(dtext, picref, width, height, dtext->fontcolor_rgba,
00682                            dtext->fontcolor, 0, 0)) < 0)
00683         return ret;
00684 
00685     return 0;
00686 }
00687 
00688 static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
00689 
00690 static void end_frame(AVFilterLink *inlink)
00691 {
00692     AVFilterLink *outlink = inlink->dst->outputs[0];
00693     AVFilterBufferRef *picref = inlink->cur_buf;
00694 
00695     draw_text(inlink->dst, picref, picref->video->w, picref->video->h);
00696 
00697     avfilter_draw_slice(outlink, 0, picref->video->h, 1);
00698     avfilter_end_frame(outlink);
00699 }
00700 
00701 AVFilter avfilter_vf_drawtext = {
00702     .name          = "drawtext",
00703     .description   = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
00704     .priv_size     = sizeof(DrawTextContext),
00705     .init          = init,
00706     .uninit        = uninit,
00707     .query_formats = query_formats,
00708 
00709     .inputs    = (AVFilterPad[]) {{ .name             = "default",
00710                                     .type             = AVMEDIA_TYPE_VIDEO,
00711                                     .get_video_buffer = avfilter_null_get_video_buffer,
00712                                     .start_frame      = avfilter_null_start_frame,
00713                                     .draw_slice       = null_draw_slice,
00714                                     .end_frame        = end_frame,
00715                                     .config_props     = config_input,
00716                                     .min_perms        = AV_PERM_WRITE |
00717                                                         AV_PERM_READ,
00718                                     .rej_perms        = AV_PERM_PRESERVE },
00719                                   { .name = NULL}},
00720     .outputs   = (AVFilterPad[]) {{ .name             = "default",
00721                                     .type             = AVMEDIA_TYPE_VIDEO, },
00722                                   { .name = NULL}},
00723 };

Generated on Wed Apr 11 2012 07:31:36 for FFmpeg by  doxygen 1.7.1