FFmpeg: libavfilter/vf_drawtext.c Source File

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 "config.h"
00033 #include "libavutil/avstring.h"
00034 #include "libavutil/common.h"
00035 #include "libavutil/file.h"
00036 #include "libavutil/eval.h"
00037 #include "libavutil/opt.h"
00038 #include "libavutil/random_seed.h"
00039 #include "libavutil/parseutils.h"
00040 #include "libavutil/timecode.h"
00041 #include "libavutil/tree.h"
00042 #include "libavutil/lfg.h"
00043 #include "avfilter.h"
00044 #include "drawutils.h"
00045 #include "formats.h"
00046 #include "internal.h"
00047 #include "video.h"
00048 
00049 #undef time
00050 
00051 #include <ft2build.h>
00052 #include <freetype/config/ftheader.h>
00053 #include FT_FREETYPE_H
00054 #include FT_GLYPH_H
00055 #if CONFIG_FONTCONFIG
00056 #include <fontconfig/fontconfig.h>
00057 #endif
00058 
00059 static const char *const var_names[] = {
00060     "dar",
00061     "hsub", "vsub",
00062     "line_h", "lh",           
00063     "main_h", "h", "H",       
00064     "main_w", "w", "W",       
00065     "max_glyph_a", "ascent",  
00066     "max_glyph_d", "descent", 
00067     "max_glyph_h",            
00068     "max_glyph_w",            
00069     "n",                      
00070     "sar",
00071     "t",                      
00072     "text_h", "th",           
00073     "text_w", "tw",           
00074     "x",
00075     "y",
00076     NULL
00077 };
00078 
00079 static const char *const fun2_names[] = {
00080     "rand"
00081 };
00082 
00083 static double drand(void *opaque, double min, double max)
00084 {
00085     return min + (max-min) / UINT_MAX * av_lfg_get(opaque);
00086 }
00087 
00088 typedef double (*eval_func2)(void *, double a, double b);
00089 
00090 static const eval_func2 fun2[] = {
00091     drand,
00092     NULL
00093 };
00094 
00095 enum var_name {
00096     VAR_DAR,
00097     VAR_HSUB, VAR_VSUB,
00098     VAR_LINE_H, VAR_LH,
00099     VAR_MAIN_H, VAR_h, VAR_H,
00100     VAR_MAIN_W, VAR_w, VAR_W,
00101     VAR_MAX_GLYPH_A, VAR_ASCENT,
00102     VAR_MAX_GLYPH_D, VAR_DESCENT,
00103     VAR_MAX_GLYPH_H,
00104     VAR_MAX_GLYPH_W,
00105     VAR_N,
00106     VAR_SAR,
00107     VAR_T,
00108     VAR_TEXT_H, VAR_TH,
00109     VAR_TEXT_W, VAR_TW,
00110     VAR_X,
00111     VAR_Y,
00112     VAR_VARS_NB
00113 };
00114 
00115 typedef struct {
00116     const AVClass *class;
00117     int reinit;                     
00118     uint8_t *fontfile;              
00119     uint8_t *text;                  
00120     uint8_t *expanded_text;         
00121     size_t   expanded_text_size;    
00122     int ft_load_flags;              
00123     FT_Vector *positions;           
00124     size_t nb_positions;            
00125     char *textfile;                 
00126     int x;                          
00127     int y;                          
00128     int max_glyph_w;                
00129     int max_glyph_h;                
00130     int shadowx, shadowy;
00131     unsigned int fontsize;          
00132     char *fontcolor_string;         
00133     char *boxcolor_string;          
00134     char *shadowcolor_string;       
00135 
00136     short int draw_box;             
00137     int use_kerning;                
00138     int tabsize;                    
00139     int fix_bounds;                 
00140 
00141     FFDrawContext dc;
00142     FFDrawColor fontcolor;          
00143     FFDrawColor shadowcolor;        
00144     FFDrawColor boxcolor;           
00145 
00146     FT_Library library;             
00147     FT_Face face;                   
00148     struct AVTreeNode *glyphs;      
00149     char *x_expr;                   
00150     char *y_expr;                   
00151     AVExpr *x_pexpr, *y_pexpr;      
00152     int64_t basetime;               
00153     double var_values[VAR_VARS_NB];
00154     char   *draw_expr;              
00155     AVExpr *draw_pexpr;             
00156     int draw;                       
00157     AVLFG  prng;                    
00158     char       *tc_opt_string;      
00159     AVRational  tc_rate;            
00160     AVTimecode  tc;                 
00161     int tc24hmax;                   
00162     int frame_id;
00163 } DrawTextContext;
00164 
00165 #define OFFSET(x) offsetof(DrawTextContext, x)
00166 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
00167 
00168 static const AVOption drawtext_options[]= {
00169 {"fontfile", "set font file",        OFFSET(fontfile),           AV_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX, FLAGS},
00170 {"text",     "set text",             OFFSET(text),               AV_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX, FLAGS},
00171 {"textfile", "set text file",        OFFSET(textfile),           AV_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX, FLAGS},
00172 {"fontcolor",   "set foreground color", OFFSET(fontcolor_string),   AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
00173 {"boxcolor",    "set box color",        OFFSET(boxcolor_string),    AV_OPT_TYPE_STRING, {.str="white"}, CHAR_MIN, CHAR_MAX, FLAGS},
00174 {"shadowcolor", "set shadow color",     OFFSET(shadowcolor_string), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
00175 {"box",      "set box",              OFFSET(draw_box),           AV_OPT_TYPE_INT,    {.i64=0},     0,        1       , FLAGS},
00176 {"fontsize", "set font size",        OFFSET(fontsize),           AV_OPT_TYPE_INT,    {.i64=0},     0,        INT_MAX , FLAGS},
00177 {"x",        "set x expression",     OFFSET(x_expr),             AV_OPT_TYPE_STRING, {.str="0"},   CHAR_MIN, CHAR_MAX, FLAGS},
00178 {"y",        "set y expression",     OFFSET(y_expr),             AV_OPT_TYPE_STRING, {.str="0"},   CHAR_MIN, CHAR_MAX, FLAGS},
00179 {"shadowx",  "set x",                OFFSET(shadowx),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN,  INT_MAX , FLAGS},
00180 {"shadowy",  "set y",                OFFSET(shadowy),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN,  INT_MAX , FLAGS},
00181 {"tabsize",  "set tab size",         OFFSET(tabsize),            AV_OPT_TYPE_INT,    {.i64=4},     0,        INT_MAX , FLAGS},
00182 {"basetime", "set base time",        OFFSET(basetime),           AV_OPT_TYPE_INT64,  {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX , FLAGS},
00183 {"draw",     "if false do not draw", OFFSET(draw_expr),          AV_OPT_TYPE_STRING, {.str="1"},   CHAR_MIN, CHAR_MAX, FLAGS},
00184 {"timecode", "set initial timecode", OFFSET(tc_opt_string),      AV_OPT_TYPE_STRING, {.str=NULL},  CHAR_MIN, CHAR_MAX, FLAGS},
00185 {"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_INT,  {.i64=0},            0,        1, FLAGS},
00186 {"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate),   AV_OPT_TYPE_RATIONAL, {.dbl=0},          0,  INT_MAX, FLAGS},
00187 {"r",        "set rate (timecode only)", OFFSET(tc_rate),        AV_OPT_TYPE_RATIONAL, {.dbl=0},          0,  INT_MAX, FLAGS},
00188 {"rate",     "set rate (timecode only)", OFFSET(tc_rate),        AV_OPT_TYPE_RATIONAL, {.dbl=0},          0,  INT_MAX, FLAGS},
00189 {"fix_bounds", "if true, check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS},
00190 
00191 /* FT_LOAD_* flags */
00192 {"ft_load_flags", "set font loading flags for libfreetype",   OFFSET(ft_load_flags),  AV_OPT_TYPE_FLAGS,  {.i64=FT_LOAD_DEFAULT|FT_LOAD_RENDER}, 0, INT_MAX, FLAGS, "ft_load_flags"},
00193 {"default",                     "set default",                     0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_DEFAULT},                     INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00194 {"no_scale",                    "set no_scale",                    0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_NO_SCALE},                    INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00195 {"no_hinting",                  "set no_hinting",                  0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_NO_HINTING},                  INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00196 {"render",                      "set render",                      0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_RENDER},                      INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00197 {"no_bitmap",                   "set no_bitmap",                   0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_NO_BITMAP},                   INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00198 {"vertical_layout",             "set vertical_layout",             0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_VERTICAL_LAYOUT},             INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00199 {"force_autohint",              "set force_autohint",              0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_FORCE_AUTOHINT},              INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00200 {"crop_bitmap",                 "set crop_bitmap",                 0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_CROP_BITMAP},                 INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00201 {"pedantic",                    "set pedantic",                    0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_PEDANTIC},                    INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00202 {"ignore_global_advance_width", "set ignore_global_advance_width", 0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH}, INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00203 {"no_recurse",                  "set no_recurse",                  0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_NO_RECURSE},                  INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00204 {"ignore_transform",            "set ignore_transform",            0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_IGNORE_TRANSFORM},            INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00205 {"monochrome",                  "set monochrome",                  0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_MONOCHROME},                  INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00206 {"linear_design",               "set linear_design",               0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_LINEAR_DESIGN},               INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00207 {"no_autohint",                 "set no_autohint",                 0, AV_OPT_TYPE_CONST, {.i64=FT_LOAD_NO_AUTOHINT},                 INT_MIN, INT_MAX, FLAGS, "ft_load_flags"},
00208 {NULL},
00209 };
00210 
00211 AVFILTER_DEFINE_CLASS(drawtext);
00212 
00213 #undef __FTERRORS_H__
00214 #define FT_ERROR_START_LIST {
00215 #define FT_ERRORDEF(e, v, s) { (e), (s) },
00216 #define FT_ERROR_END_LIST { 0, NULL } };
00217 
00218 struct ft_error
00219 {
00220     int err;
00221     const char *err_msg;
00222 } static ft_errors[] =
00223 #include FT_ERRORS_H
00224 
00225 #define FT_ERRMSG(e) ft_errors[e].err_msg
00226 
00227 typedef struct {
00228     FT_Glyph *glyph;
00229     uint32_t code;
00230     FT_Bitmap bitmap; 
00231     FT_BBox bbox;
00232     int advance;
00233     int bitmap_left;
00234     int bitmap_top;
00235 } Glyph;
00236 
00237 static int glyph_cmp(void *key, const void *b)
00238 {
00239     const Glyph *a = key, *bb = b;
00240     int64_t diff = (int64_t)a->code - (int64_t)bb->code;
00241     return diff > 0 ? 1 : diff < 0 ? -1 : 0;
00242 }
00243 
00247 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
00248 {
00249     DrawTextContext *dtext = ctx->priv;
00250     Glyph *glyph;
00251     struct AVTreeNode *node = NULL;
00252     int ret;
00253 
00254     /* load glyph into dtext->face->glyph */
00255     if (FT_Load_Char(dtext->face, code, dtext->ft_load_flags))
00256         return AVERROR(EINVAL);
00257 
00258     /* save glyph */
00259     if (!(glyph = av_mallocz(sizeof(*glyph))) ||
00260         !(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
00261         ret = AVERROR(ENOMEM);
00262         goto error;
00263     }
00264     glyph->code  = code;
00265 
00266     if (FT_Get_Glyph(dtext->face->glyph, glyph->glyph)) {
00267         ret = AVERROR(EINVAL);
00268         goto error;
00269     }
00270 
00271     glyph->bitmap      = dtext->face->glyph->bitmap;
00272     glyph->bitmap_left = dtext->face->glyph->bitmap_left;
00273     glyph->bitmap_top  = dtext->face->glyph->bitmap_top;
00274     glyph->advance     = dtext->face->glyph->advance.x >> 6;
00275 
00276     /* measure text height to calculate text_height (or the maximum text height) */
00277     FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
00278 
00279     /* cache the newly created glyph */
00280     if (!(node = av_mallocz(av_tree_node_size))) {
00281         ret = AVERROR(ENOMEM);
00282         goto error;
00283     }
00284     av_tree_insert(&dtext->glyphs, glyph, glyph_cmp, &node);
00285 
00286     if (glyph_ptr)
00287         *glyph_ptr = glyph;
00288     return 0;
00289 
00290 error:
00291     if (glyph)
00292         av_freep(&glyph->glyph);
00293     av_freep(&glyph);
00294     av_freep(&node);
00295     return ret;
00296 }
00297 
00298 static int load_font_file(AVFilterContext *ctx, const char *path, int index,
00299                           const char **error)
00300 {
00301     DrawTextContext *dtext = ctx->priv;
00302     int err;
00303 
00304     err = FT_New_Face(dtext->library, path, index, &dtext->face);
00305     if (err) {
00306         *error = FT_ERRMSG(err);
00307         return AVERROR(EINVAL);
00308     }
00309     return 0;
00310 }
00311 
00312 #if CONFIG_FONTCONFIG
00313 static int load_font_fontconfig(AVFilterContext *ctx, const char **error)
00314 {
00315     DrawTextContext *dtext = ctx->priv;
00316     FcConfig *fontconfig;
00317     FcPattern *pattern, *fpat;
00318     FcResult result = FcResultMatch;
00319     FcChar8 *filename;
00320     int err, index;
00321     double size;
00322 
00323     fontconfig = FcInitLoadConfigAndFonts();
00324     if (!fontconfig) {
00325         *error = "impossible to init fontconfig\n";
00326         return AVERROR(EINVAL);
00327     }
00328     pattern = FcNameParse(dtext->fontfile ? dtext->fontfile :
00329                           (uint8_t *)(intptr_t)"default");
00330     if (!pattern) {
00331         *error = "could not parse fontconfig pattern";
00332         return AVERROR(EINVAL);
00333     }
00334     if (!FcConfigSubstitute(fontconfig, pattern, FcMatchPattern)) {
00335         *error = "could not substitue fontconfig options"; /* very unlikely */
00336         return AVERROR(EINVAL);
00337     }
00338     FcDefaultSubstitute(pattern);
00339     fpat = FcFontMatch(fontconfig, pattern, &result);
00340     if (!fpat || result != FcResultMatch) {
00341         *error = "impossible to find a matching font";
00342         return AVERROR(EINVAL);
00343     }
00344     if (FcPatternGetString (fpat, FC_FILE,  0, &filename) != FcResultMatch ||
00345         FcPatternGetInteger(fpat, FC_INDEX, 0, &index   ) != FcResultMatch ||
00346         FcPatternGetDouble (fpat, FC_SIZE,  0, &size    ) != FcResultMatch) {
00347         *error = "impossible to find font information";
00348         return AVERROR(EINVAL);
00349     }
00350     av_log(ctx, AV_LOG_INFO, "Using \"%s\"\n", filename);
00351     if (!dtext->fontsize)
00352         dtext->fontsize = size + 0.5;
00353     err = load_font_file(ctx, filename, index, error);
00354     if (err)
00355         return err;
00356     FcPatternDestroy(fpat);
00357     FcPatternDestroy(pattern);
00358     FcConfigDestroy(fontconfig);
00359     return 0;
00360 }
00361 #endif
00362 
00363 static int load_font(AVFilterContext *ctx)
00364 {
00365     DrawTextContext *dtext = ctx->priv;
00366     int err;
00367     const char *error = "unknown error\n";
00368 
00369     /* load the face, and set up the encoding, which is by default UTF-8 */
00370     err = load_font_file(ctx, dtext->fontfile, 0, &error);
00371     if (!err)
00372         return 0;
00373 #if CONFIG_FONTCONFIG
00374     err = load_font_fontconfig(ctx, &error);
00375     if (!err)
00376         return 0;
00377 #endif
00378     av_log(ctx, AV_LOG_ERROR, "Could not load font \"%s\": %s\n",
00379            dtext->fontfile, error);
00380     return err;
00381 }
00382 
00383 static av_cold int init(AVFilterContext *ctx, const char *args)
00384 {
00385     int err;
00386     DrawTextContext *dtext = ctx->priv;
00387     Glyph *glyph;
00388 
00389     dtext->class = &drawtext_class;
00390     av_opt_set_defaults(dtext);
00391 
00392     if ((err = av_set_options_string(dtext, args, "=", ":")) < 0)
00393         return err;
00394 
00395     if (!dtext->fontfile && !CONFIG_FONTCONFIG) {
00396         av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
00397         return AVERROR(EINVAL);
00398     }
00399 
00400     if (dtext->textfile) {
00401         uint8_t *textbuf;
00402         size_t textbuf_size;
00403 
00404         if (dtext->text) {
00405             av_log(ctx, AV_LOG_ERROR,
00406                    "Both text and text file provided. Please provide only one\n");
00407             return AVERROR(EINVAL);
00408         }
00409         if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
00410             av_log(ctx, AV_LOG_ERROR,
00411                    "The text file '%s' could not be read or is empty\n",
00412                    dtext->textfile);
00413             return err;
00414         }
00415 
00416         if (!(dtext->text = av_malloc(textbuf_size+1)))
00417             return AVERROR(ENOMEM);
00418         memcpy(dtext->text, textbuf, textbuf_size);
00419         dtext->text[textbuf_size] = 0;
00420         av_file_unmap(textbuf, textbuf_size);
00421     }
00422 
00423     if (dtext->tc_opt_string) {
00424         int ret = av_timecode_init_from_string(&dtext->tc, dtext->tc_rate,
00425                                                dtext->tc_opt_string, ctx);
00426         if (ret < 0)
00427             return ret;
00428         if (dtext->tc24hmax)
00429             dtext->tc.flags |= AV_TIMECODE_FLAG_24HOURSMAX;
00430         if (!dtext->text)
00431             dtext->text = av_strdup("");
00432     }
00433 
00434     if (!dtext->text) {
00435         av_log(ctx, AV_LOG_ERROR,
00436                "Either text, a valid file or a timecode must be provided\n");
00437         return AVERROR(EINVAL);
00438     }
00439 
00440     if ((err = av_parse_color(dtext->fontcolor.rgba, dtext->fontcolor_string, -1, ctx))) {
00441         av_log(ctx, AV_LOG_ERROR,
00442                "Invalid font color '%s'\n", dtext->fontcolor_string);
00443         return err;
00444     }
00445 
00446     if ((err = av_parse_color(dtext->boxcolor.rgba, dtext->boxcolor_string, -1, ctx))) {
00447         av_log(ctx, AV_LOG_ERROR,
00448                "Invalid box color '%s'\n", dtext->boxcolor_string);
00449         return err;
00450     }
00451 
00452     if ((err = av_parse_color(dtext->shadowcolor.rgba, dtext->shadowcolor_string, -1, ctx))) {
00453         av_log(ctx, AV_LOG_ERROR,
00454                "Invalid shadow color '%s'\n", dtext->shadowcolor_string);
00455         return err;
00456     }
00457 
00458     if ((err = FT_Init_FreeType(&(dtext->library)))) {
00459         av_log(ctx, AV_LOG_ERROR,
00460                "Could not load FreeType: %s\n", FT_ERRMSG(err));
00461         return AVERROR(EINVAL);
00462     }
00463 
00464     err = load_font(ctx);
00465     if (err)
00466         return err;
00467     if (!dtext->fontsize)
00468         dtext->fontsize = 16;
00469     if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
00470         av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
00471                dtext->fontsize, FT_ERRMSG(err));
00472         return AVERROR(EINVAL);
00473     }
00474 
00475     dtext->use_kerning = FT_HAS_KERNING(dtext->face);
00476 
00477     /* load the fallback glyph with code 0 */
00478     load_glyph(ctx, NULL, 0);
00479 
00480     /* set the tabsize in pixels */
00481     if ((err = load_glyph(ctx, &glyph, ' ')) < 0) {
00482         av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
00483         return err;
00484     }
00485     dtext->tabsize *= glyph->advance;
00486 
00487     return 0;
00488 }
00489 
00490 static int query_formats(AVFilterContext *ctx)
00491 {
00492     ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
00493     return 0;
00494 }
00495 
00496 static int glyph_enu_free(void *opaque, void *elem)
00497 {
00498     Glyph *glyph = elem;
00499 
00500     FT_Done_Glyph(*glyph->glyph);
00501     av_freep(&glyph->glyph);
00502     av_free(elem);
00503     return 0;
00504 }
00505 
00506 static av_cold void uninit(AVFilterContext *ctx)
00507 {
00508     DrawTextContext *dtext = ctx->priv;
00509 
00510     av_expr_free(dtext->x_pexpr); dtext->x_pexpr = NULL;
00511     av_expr_free(dtext->y_pexpr); dtext->y_pexpr = NULL;
00512     av_expr_free(dtext->draw_pexpr); dtext->draw_pexpr = NULL;
00513     av_opt_free(dtext);
00514 
00515     av_freep(&dtext->positions);
00516     dtext->nb_positions = 0;
00517 
00518     av_tree_enumerate(dtext->glyphs, NULL, NULL, glyph_enu_free);
00519     av_tree_destroy(dtext->glyphs);
00520     dtext->glyphs = NULL;
00521 
00522     FT_Done_Face(dtext->face);
00523     FT_Done_FreeType(dtext->library);
00524 }
00525 
00526 static inline int is_newline(uint32_t c)
00527 {
00528     return c == '\n' || c == '\r' || c == '\f' || c == '\v';
00529 }
00530 
00531 static int config_input(AVFilterLink *inlink)
00532 {
00533     AVFilterContext *ctx = inlink->dst;
00534     DrawTextContext *dtext = ctx->priv;
00535     int ret;
00536 
00537     ff_draw_init(&dtext->dc, inlink->format, 0);
00538     ff_draw_color(&dtext->dc, &dtext->fontcolor,   dtext->fontcolor.rgba);
00539     ff_draw_color(&dtext->dc, &dtext->shadowcolor, dtext->shadowcolor.rgba);
00540     ff_draw_color(&dtext->dc, &dtext->boxcolor,    dtext->boxcolor.rgba);
00541 
00542     dtext->var_values[VAR_w]     = dtext->var_values[VAR_W]     = dtext->var_values[VAR_MAIN_W] = inlink->w;
00543     dtext->var_values[VAR_h]     = dtext->var_values[VAR_H]     = dtext->var_values[VAR_MAIN_H] = inlink->h;
00544     dtext->var_values[VAR_SAR]   = inlink->sample_aspect_ratio.num ? av_q2d(inlink->sample_aspect_ratio) : 1;
00545     dtext->var_values[VAR_DAR]   = (double)inlink->w / inlink->h * dtext->var_values[VAR_SAR];
00546     dtext->var_values[VAR_HSUB]  = 1 << dtext->dc.hsub_max;
00547     dtext->var_values[VAR_VSUB]  = 1 << dtext->dc.vsub_max;
00548     dtext->var_values[VAR_X]     = NAN;
00549     dtext->var_values[VAR_Y]     = NAN;
00550     if (!dtext->reinit)
00551         dtext->var_values[VAR_N] = 0;
00552     dtext->var_values[VAR_T]     = NAN;
00553 
00554     av_lfg_init(&dtext->prng, av_get_random_seed());
00555 
00556     if ((ret = av_expr_parse(&dtext->x_pexpr, dtext->x_expr, var_names,
00557                              NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
00558         (ret = av_expr_parse(&dtext->y_pexpr, dtext->y_expr, var_names,
00559                              NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
00560         (ret = av_expr_parse(&dtext->draw_pexpr, dtext->draw_expr, var_names,
00561                              NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
00562 
00563         return AVERROR(EINVAL);
00564 
00565     return 0;
00566 }
00567 
00568 static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
00569 {
00570     DrawTextContext *dtext = ctx->priv;
00571 
00572     if (!strcmp(cmd, "reinit")) {
00573         int ret;
00574         uninit(ctx);
00575         dtext->reinit = 1;
00576         if ((ret = init(ctx, arg)) < 0)
00577             return ret;
00578         return config_input(ctx->inputs[0]);
00579     }
00580 
00581     return AVERROR(ENOSYS);
00582 }
00583 
00584 static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
00585                        int width, int height, const uint8_t rgbcolor[4], FFDrawColor *color, int x, int y)
00586 {
00587     char *text = dtext->expanded_text;
00588     uint32_t code = 0;
00589     int i, x1, y1;
00590     uint8_t *p;
00591     Glyph *glyph = NULL;
00592 
00593     for (i = 0, p = text; *p; i++) {
00594         Glyph dummy = { 0 };
00595         GET_UTF8(code, *p++, continue;);
00596 
00597         /* skip new line chars, just go to new line */
00598         if (code == '\n' || code == '\r' || code == '\t')
00599             continue;
00600 
00601         dummy.code = code;
00602         glyph = av_tree_find(dtext->glyphs, &dummy, (void *)glyph_cmp, NULL);
00603 
00604         if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
00605             glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
00606             return AVERROR(EINVAL);
00607 
00608         x1 = dtext->positions[i].x+dtext->x+x;
00609         y1 = dtext->positions[i].y+dtext->y+y;
00610 
00611         ff_blend_mask(&dtext->dc, color,
00612                       picref->data, picref->linesize, width, height,
00613                       glyph->bitmap.buffer, glyph->bitmap.pitch,
00614                       glyph->bitmap.width, glyph->bitmap.rows,
00615                       glyph->bitmap.pixel_mode == FT_PIXEL_MODE_MONO ? 0 : 3,
00616                       0, x1, y1);
00617     }
00618 
00619     return 0;
00620 }
00621 
00622 static int draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref,
00623                      int width, int height)
00624 {
00625     DrawTextContext *dtext = ctx->priv;
00626     uint32_t code = 0, prev_code = 0;
00627     int x = 0, y = 0, i = 0, ret;
00628     int max_text_line_w = 0, len;
00629     int box_w, box_h;
00630     char *text = dtext->text;
00631     uint8_t *p;
00632     int y_min = 32000, y_max = -32000;
00633     int x_min = 32000, x_max = -32000;
00634     FT_Vector delta;
00635     Glyph *glyph = NULL, *prev_glyph = NULL;
00636     Glyph dummy = { 0 };
00637 
00638     time_t now = time(0);
00639     struct tm ltime;
00640     uint8_t *buf = dtext->expanded_text;
00641     int buf_size = dtext->expanded_text_size;
00642 
00643     if(dtext->basetime != AV_NOPTS_VALUE)
00644         now= picref->pts*av_q2d(ctx->inputs[0]->time_base) + dtext->basetime/1000000;
00645 
00646     if (!buf) {
00647         buf_size = 2*strlen(dtext->text)+1;
00648         buf = av_malloc(buf_size);
00649     }
00650 
00651 #if HAVE_LOCALTIME_R
00652     localtime_r(&now, &ltime);
00653 #else
00654     if(strchr(dtext->text, '%'))
00655         ltime= *localtime(&now);
00656 #endif
00657 
00658     do {
00659         *buf = 1;
00660         if (strftime(buf, buf_size, dtext->text, &ltime) != 0 || *buf == 0)
00661             break;
00662         buf_size *= 2;
00663     } while ((buf = av_realloc(buf, buf_size)));
00664 
00665     if (dtext->tc_opt_string) {
00666         char tcbuf[AV_TIMECODE_STR_SIZE];
00667         av_timecode_make_string(&dtext->tc, tcbuf, dtext->frame_id++);
00668         buf = av_asprintf("%s%s", dtext->text, tcbuf);
00669     }
00670 
00671     if (!buf)
00672         return AVERROR(ENOMEM);
00673     text = dtext->expanded_text = buf;
00674     dtext->expanded_text_size = buf_size;
00675     if ((len = strlen(text)) > dtext->nb_positions) {
00676         if (!(dtext->positions =
00677               av_realloc(dtext->positions, len*sizeof(*dtext->positions))))
00678             return AVERROR(ENOMEM);
00679         dtext->nb_positions = len;
00680     }
00681 
00682     x = 0;
00683     y = 0;
00684 
00685     /* load and cache glyphs */
00686     for (i = 0, p = text; *p; i++) {
00687         GET_UTF8(code, *p++, continue;);
00688 
00689         /* get glyph */
00690         dummy.code = code;
00691         glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
00692         if (!glyph) {
00693             load_glyph(ctx, &glyph, code);
00694         }
00695 
00696         y_min = FFMIN(glyph->bbox.yMin, y_min);
00697         y_max = FFMAX(glyph->bbox.yMax, y_max);
00698         x_min = FFMIN(glyph->bbox.xMin, x_min);
00699         x_max = FFMAX(glyph->bbox.xMax, x_max);
00700     }
00701     dtext->max_glyph_h = y_max - y_min;
00702     dtext->max_glyph_w = x_max - x_min;
00703 
00704     /* compute and save position for each glyph */
00705     glyph = NULL;
00706     for (i = 0, p = text; *p; i++) {
00707         GET_UTF8(code, *p++, continue;);
00708 
00709         /* skip the \n in the sequence \r\n */
00710         if (prev_code == '\r' && code == '\n')
00711             continue;
00712 
00713         prev_code = code;
00714         if (is_newline(code)) {
00715             max_text_line_w = FFMAX(max_text_line_w, x);
00716             y += dtext->max_glyph_h;
00717             x = 0;
00718             continue;
00719         }
00720 
00721         /* get glyph */
00722         prev_glyph = glyph;
00723         dummy.code = code;
00724         glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
00725 
00726         /* kerning */
00727         if (dtext->use_kerning && prev_glyph && glyph->code) {
00728             FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
00729                            ft_kerning_default, &delta);
00730             x += delta.x >> 6;
00731         }
00732 
00733         /* save position */
00734         dtext->positions[i].x = x + glyph->bitmap_left;
00735         dtext->positions[i].y = y - glyph->bitmap_top + y_max;
00736         if (code == '\t') x  = (x / dtext->tabsize + 1)*dtext->tabsize;
00737         else              x += glyph->advance;
00738     }
00739 
00740     max_text_line_w = FFMAX(x, max_text_line_w);
00741 
00742     dtext->var_values[VAR_TW] = dtext->var_values[VAR_TEXT_W] = max_text_line_w;
00743     dtext->var_values[VAR_TH] = dtext->var_values[VAR_TEXT_H] = y + dtext->max_glyph_h;
00744 
00745     dtext->var_values[VAR_MAX_GLYPH_W] = dtext->max_glyph_w;
00746     dtext->var_values[VAR_MAX_GLYPH_H] = dtext->max_glyph_h;
00747     dtext->var_values[VAR_MAX_GLYPH_A] = dtext->var_values[VAR_ASCENT ] = y_max;
00748     dtext->var_values[VAR_MAX_GLYPH_D] = dtext->var_values[VAR_DESCENT] = y_min;
00749 
00750     dtext->var_values[VAR_LINE_H] = dtext->var_values[VAR_LH] = dtext->max_glyph_h;
00751 
00752     dtext->x = dtext->var_values[VAR_X] = av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
00753     dtext->y = dtext->var_values[VAR_Y] = av_expr_eval(dtext->y_pexpr, dtext->var_values, &dtext->prng);
00754     dtext->x = dtext->var_values[VAR_X] = av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
00755     dtext->draw = av_expr_eval(dtext->draw_pexpr, dtext->var_values, &dtext->prng);
00756 
00757     if(!dtext->draw)
00758         return 0;
00759 
00760     box_w = FFMIN(width - 1 , max_text_line_w);
00761     box_h = FFMIN(height - 1, y + dtext->max_glyph_h);
00762 
00763     /* draw box */
00764     if (dtext->draw_box)
00765         ff_blend_rectangle(&dtext->dc, &dtext->boxcolor,
00766                            picref->data, picref->linesize, width, height,
00767                            dtext->x, dtext->y, box_w, box_h);
00768 
00769     if (dtext->shadowx || dtext->shadowy) {
00770         if ((ret = draw_glyphs(dtext, picref, width, height, dtext->shadowcolor.rgba,
00771                                &dtext->shadowcolor, dtext->shadowx, dtext->shadowy)) < 0)
00772             return ret;
00773     }
00774 
00775     if ((ret = draw_glyphs(dtext, picref, width, height, dtext->fontcolor.rgba,
00776                            &dtext->fontcolor, 0, 0)) < 0)
00777         return ret;
00778 
00779     return 0;
00780 }
00781 
00782 static int null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
00783 {
00784     return 0;
00785 }
00786 
00787 static int end_frame(AVFilterLink *inlink)
00788 {
00789     AVFilterContext *ctx = inlink->dst;
00790     AVFilterLink *outlink = ctx->outputs[0];
00791     DrawTextContext *dtext = ctx->priv;
00792     AVFilterBufferRef *picref = inlink->cur_buf;
00793     int ret;
00794 
00795     dtext->var_values[VAR_T] = picref->pts == AV_NOPTS_VALUE ?
00796         NAN : picref->pts * av_q2d(inlink->time_base);
00797 
00798     draw_text(ctx, picref, picref->video->w, picref->video->h);
00799 
00800     av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
00801            (int)dtext->var_values[VAR_N], dtext->var_values[VAR_T],
00802            (int)dtext->var_values[VAR_TEXT_W], (int)dtext->var_values[VAR_TEXT_H],
00803            dtext->x, dtext->y);
00804 
00805     dtext->var_values[VAR_N] += 1.0;
00806 
00807     if ((ret = ff_draw_slice(outlink, 0, picref->video->h, 1)) < 0 ||
00808         (ret = ff_end_frame(outlink)) < 0)
00809         return ret;
00810     return 0;
00811 }
00812 
00813 AVFilter avfilter_vf_drawtext = {
00814     .name          = "drawtext",
00815     .description   = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
00816     .priv_size     = sizeof(DrawTextContext),
00817     .init          = init,
00818     .uninit        = uninit,
00819     .query_formats = query_formats,
00820 
00821     .inputs    = (const AVFilterPad[]) {{ .name             = "default",
00822                                           .type             = AVMEDIA_TYPE_VIDEO,
00823                                           .get_video_buffer = ff_null_get_video_buffer,
00824                                           .start_frame      = ff_null_start_frame,
00825                                           .draw_slice       = null_draw_slice,
00826                                           .end_frame        = end_frame,
00827                                           .config_props     = config_input,
00828                                           .min_perms        = AV_PERM_WRITE |
00829                                                               AV_PERM_READ },
00830                                         { .name = NULL}},
00831     .outputs   = (const AVFilterPad[]) {{ .name             = "default",
00832                                           .type             = AVMEDIA_TYPE_VIDEO, },
00833                                         { .name = NULL}},
00834     .process_command = command,
00835     .priv_class = &drawtext_class,
00836 };