[FFmpeg-devel] [PATCH] Add drawtext filter from the libavfilter soc repo.

Stefano Sabatini stefano.sabatini-lala
Tue Sep 28 16:17:00 CEST 2010


---
 configure                 |    6 +
 doc/filters.texi          |   81 ++++++++
 libavfilter/Makefile      |    1 +
 libavfilter/allfilters.c  |    1 +
 libavfilter/vf_drawtext.c |  494 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 583 insertions(+), 0 deletions(-)
 create mode 100644 libavfilter/vf_drawtext.c

diff --git a/configure b/configure
index 21ea161..6a9971c 100755
--- a/configure
+++ b/configure
@@ -170,6 +170,7 @@ External library support:
                            and libraw1394 [no]
   --enable-libdirac        enable Dirac support via libdirac [no]
   --enable-libfaac         enable FAAC support via libfaac [no]
+  --enable-libfreetype     enable libfreetype [no]
   --enable-libgsm          enable GSM support via libgsm [no]
   --enable-libmp3lame      enable MP3 encoding via libmp3lame [no]
   --enable-libnut          enable NUT (de)muxing via libnut,
@@ -885,6 +886,7 @@ CONFIG_LIST="
     libdc1394
     libdirac
     libfaac
+    libfreetype
     libgsm
     libmp3lame
     libnut
@@ -1029,6 +1031,7 @@ HAVE_LIST="
     llrintf
     local_aligned_16
     local_aligned_8
+    localtime_r
     log2
     log2f
     loongson
@@ -1399,6 +1402,7 @@ udp_protocol_deps="network"
 
 # filters
 blackframe_filter_deps="gpl"
+drawtext_filter_deps="libfreetype"
 frei0r_filter_deps="frei0r dlopen strtok_r"
 ocv_smooth_filter_deps="libopencv"
 yadif_filter_deps="gpl"
@@ -2657,6 +2661,7 @@ check_func  getrusage
 check_struct "sys/time.h sys/resource.h" "struct rusage" ru_maxrss
 check_func  inet_aton $network_extralibs
 check_func  isatty
+check_func  localtime_r
 check_func  ${malloc_prefix}memalign            && enable memalign
 check_func  mkstemp
 check_func  ${malloc_prefix}posix_memalign      && enable posix_memalign
@@ -2741,6 +2746,7 @@ enabled libdirac   && add_cflags $(pkg-config --cflags dirac) &&
                       require  libdirac libdirac_decoder/dirac_parser.h dirac_decoder_init $(pkg-config --libs dirac) &&
                       require  libdirac libdirac_encoder/dirac_encoder.h dirac_encoder_init $(pkg-config --libs dirac)
 enabled libfaac    && require2 libfaac "stdint.h faac.h" faacEncGetVersion -lfaac
+enabled libfreetype && add_cflags $(pkg-config --cflags freetype2) && require libfreetype ft2build.h FT_Init_FreeType -lfreetype -lz
 enabled libgsm     && require  libgsm gsm/gsm.h gsm_create -lgsm
 enabled libmp3lame && require  "libmp3lame >= 3.98.3" lame/lame.h hip_decode_init -lmp3lame
 enabled libnut     && require  libnut libnut.h nut_demuxer_init -lnut
diff --git a/doc/filters.texi b/doc/filters.texi
index e4c1851..79fc9c4 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -222,6 +222,87 @@ drawbox
 drawbox=10:20:200:60:red@@0.5"
 @end example
 
+ at section drawtext
+
+Draw text string or text from specified file on top of video using the
+libfreetype library.
+The filter also recognizes strftime() sequences in the provided text and
+expands them accordingly. Check the documentation of strftime().
+
+To enable compilation of this filter you need to configure FFmpeg with
+--enable-libfreetype.
+
+The filter accepts parameters as a list of @var{key}=@var{value} pairs,
+separated by ":".
+
+The description of the accepted parameters follows.
+
+ at table @option
+
+ at item fontfile
+The font file to be used for drawing text. Path must be included.
+This parameter is mandatory.
+
+ at item text
+The text string to be drawn.
+This parameter is mandatory if no file is specified.
+
+ at item textfile
+A text file containing text to be drawn. Max of 1024 characters are
+read from the file.
+
+This parameter is mandatory if no text string is specified.
+
+If both text and textfile are specified, an error is thrown.
+
+ at item x, y
+The offsets where text will be drawn within the video frame.
+Relative to the top/left border of the output image.
+
+The default value of @var{x} and @var{y} is 0.
+
+ at item fontsize
+The font size to be used for drawing text.
+The default value of @var{size} is 16.
+
+ at item fgcolor
+The foreground color to be used for drawing text.
+Either a string (e.g. "red") or in 0xRRGGBB[AA] format
+(e.g. "0xff000033"), possibly followed by an alpha specifier.
+The default value of @var{fgcolor} is "black".
+
+ at item bgcolor
+The background color to be used for drawing box around text or drawing
+text outline based on option selected.
+Either a string (e.g. "yellow") or in 0xRRGGBB[AA] format
+(e.g. "0xff00ff"), possibly followed by an alpha specifier.
+
+The default value of @var{bgcolor} is "white".
+
+ at item box
+Used to draw a box around text using background color.
+Value should be either 1 (enable) or 0 (disable).
+The default value of @var{box} is 0.
+
+ at item outline
+Used to draw an outline around text using background color.
+Value should be either 1 (enable) or 0 (disable).
+The default value of @var{outline} is 0.
+
+ at end table
+
+ at example
+drawtext="fontfile=FreeSerif.ttf: text='Test Text': x=100: y=50: fontsize=24:
+          fgcolor=yellow@@0.2: bgcolor=red@@0.2: box=1"
+ at end example
+
+Draw 'Test Text' with font FreeSerif of size 24 at (100,50), text color is yellow,
+background color is red, draw a box around text. Both the text and the
+box have an opacity of 20%.
+
+Note that the double quotes are not necessary if spaces are not used within
+the parameter list.
+
 @section fifo
 
 Buffer input images and send them when they are requested.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 74e55bb..6ea60f3 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -24,6 +24,7 @@ OBJS-$(CONFIG_ASPECT_FILTER)                 += vf_aspect.o
 OBJS-$(CONFIG_BLACKFRAME_FILTER)             += vf_blackframe.o
 OBJS-$(CONFIG_CROP_FILTER)                   += vf_crop.o
 OBJS-$(CONFIG_DRAWBOX_FILTER)                += vf_drawbox.o
+OBJS-$(CONFIG_DRAWTEXT_FILTER)               += vf_drawtext.o
 OBJS-$(CONFIG_FIFO_FILTER)                   += vf_fifo.o
 OBJS-$(CONFIG_FORMAT_FILTER)                 += vf_format.o
 OBJS-$(CONFIG_FREI0R_FILTER)                 += vf_frei0r.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index c5da648..dbc0581 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -44,6 +44,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER (BLACKFRAME,  blackframe,  vf);
     REGISTER_FILTER (CROP,        crop,        vf);
     REGISTER_FILTER (DRAWBOX,     drawbox,     vf);
+    REGISTER_FILTER (DRAWTEXT,    drawtext,    vf);
     REGISTER_FILTER (FIFO,        fifo,        vf);
     REGISTER_FILTER (FORMAT,      format,      vf);
     REGISTER_FILTER (FREI0R,      frei0r,      vf);
diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c
new file mode 100644
index 0000000..6d7b77b
--- /dev/null
+++ b/libavfilter/vf_drawtext.c
@@ -0,0 +1,494 @@
+/*
+ * Copyright (C) 2010 S.N. Hemanth Meenakshisundaram
+ * Copyright (C) 2003 Gustavo Sverzut Barbieri <gsbarbieri at yahoo.com.br>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Drawtext Filter.
+ * Based on the original FFmpeg vhook/drawtext.c filter by Gustavo
+ * Sverzut Barbieri.
+ */
+
+#include "libavutil/colorspace.h"
+#include "libavutil/pixdesc.h"
+#include "avfilter.h"
+#include "parseutils.h"
+
+#undef time
+#include <sys/time.h>
+#include <time.h>
+
+#include <ft2build.h>
+#include <freetype/config/ftheader.h>
+#include FT_FREETYPE_H
+#include FT_GLYPH_H
+
+typedef struct {
+    const AVClass *class;
+    unsigned char *fontfile;        ///< font to be used
+    unsigned char *text;            ///< text to be drawn
+    char *textfile;                 ///< file with text to be drawn
+    unsigned int x;                 ///< x position to start drawing text
+    unsigned int y;                 ///< y position to start drawing text
+    unsigned int fontsize;          ///< font size to use
+    char *fgcolor_string;           ///< foreground color as string
+    char *bgcolor_string;           ///< background color as string
+    unsigned char fgcolor[4];       ///< foreground color in YUV
+    unsigned char bgcolor[4];       ///< background/Box color in YUV
+    short int draw_box;             ///< draw box around text - true or false
+    short int outline;              ///< draw outline in bg color around text
+    int text_height;                ///< height of a font symbol
+    int baseline;                   ///< baseline to draw fonts from
+    int use_kerning;                ///< font kerning is used - true/false
+    FT_Library library;             ///< freetype font library handle
+    FT_Face face;                   ///< freetype font face handle
+    FT_Glyph glyphs[256];           ///< array holding glyphs of font
+    FT_Bitmap bitmaps[256];         ///< array holding bitmaps of font
+    int advance[256];
+    int bitmap_left[256];
+    int bitmap_top[256];
+    unsigned int glyphs_index[256];
+    int hsub, vsub;                 ///< chroma subsampling values
+} DrawTextContext;
+
+#define OFFSET(x) offsetof(DrawTextContext, x)
+
+static const AVOption drawtext_options[]= {
+{"fontfile", "set font file",        OFFSET(fontfile),       FF_OPT_TYPE_STRING, 0,  CHAR_MIN, CHAR_MAX },
+{"text",     "set text",             OFFSET(text),           FF_OPT_TYPE_STRING, 0,  CHAR_MIN, CHAR_MAX },
+{"textfile", "set text file",        OFFSET(textfile),       FF_OPT_TYPE_STRING, 0,  CHAR_MIN, CHAR_MAX },
+{"fgcolor",  "set foreground color", OFFSET(fgcolor_string), FF_OPT_TYPE_STRING, 0,  CHAR_MIN, CHAR_MAX },
+{"bgcolor",  "set background color", OFFSET(bgcolor_string), FF_OPT_TYPE_STRING, 0,  CHAR_MIN, CHAR_MAX },
+{"box",      "set box",              OFFSET(draw_box),       FF_OPT_TYPE_INT,    0,         0,        1 },
+{"outline",  "set outline",          OFFSET(outline),        FF_OPT_TYPE_INT,    0,         0,        1 },
+{"fontsize", "set font size",        OFFSET(fontsize),       FF_OPT_TYPE_INT,   16,         1,       72 },
+{"x",        "set x",                OFFSET(x),              FF_OPT_TYPE_INT,    0,         0,  INT_MAX },
+{"y",        "set y",                OFFSET(y),              FF_OPT_TYPE_INT,    0,         0,  INT_MAX },
+{NULL},
+};
+
+static const char *drawtext_get_name(void *ctx)
+{
+    return "drawtext";
+}
+
+static const AVClass drawtext_class = {
+    "DrawTextContext",
+    drawtext_get_name,
+    drawtext_options
+};
+
+static int query_formats(AVFilterContext *ctx)
+{
+    /* FIXME: Add support for other formats */
+    enum PixelFormat pix_fmts[] = {
+        PIX_FMT_YUV420P, PIX_FMT_YUV444P, PIX_FMT_YUV422P,
+        PIX_FMT_YUV411P, PIX_FMT_YUV410P,
+        PIX_FMT_YUV440P, PIX_FMT_NONE
+    };
+
+    avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
+    return 0;
+}
+
+#undef __FTERRORS_H__
+#define FT_ERROR_START_LIST {
+#define FT_ERRORDEF(e, v, s) { (e), (s) },
+#define FT_ERROR_END_LIST { 0, NULL } };
+
+struct ft_error
+{
+    int err;
+    const char *err_msg;
+} static ft_errors[] =
+#include FT_ERRORS_H
+
+#define FT_ERRMSG(e) ft_errors[e].err_msg
+
+#define MAX_TEXT_SIZE 1024
+
+static inline int extract_color(AVFilterContext *ctx, char *color_str, unsigned char *color)
+{
+    uint8_t rgba[4];
+    uint8_t err;
+    if ((err = av_parse_color(rgba, color_str, ctx))) {
+        return err;
+    }
+    color[0] = RGB_TO_Y(rgba[0], rgba[1], rgba[2]);
+    color[1] = RGB_TO_U(rgba[0], rgba[1], rgba[2], 0);
+    color[2] = RGB_TO_V(rgba[0], rgba[1], rgba[2], 0);
+    color[3] = rgba[3];
+
+    return 0;
+}
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    unsigned short int c;
+    int err;
+    int y_max, y_min;
+    FT_BBox bbox;
+    DrawTextContext *dtext = ctx->priv;
+
+    dtext->class = &drawtext_class;
+    av_opt_set_defaults2(dtext, 0, 0);
+    dtext->fgcolor_string = av_strdup("black");
+    dtext->bgcolor_string = av_strdup("white");
+
+    if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
+        return err;
+    }
+
+    if (!dtext->fontfile) {
+        av_log(ctx, AV_LOG_ERROR, "No font file provided! (=fontfile:<filename>)\n");
+        return AVERROR(EINVAL);
+    }
+
+    if (dtext->textfile) {
+        FILE *fp;
+        if (dtext->text) {
+            av_log(ctx, AV_LOG_ERROR, "Both text and file provided. Please provide only one.\n");
+            return AVERROR(EINVAL);
+        }
+        if (!(fp = fopen(dtext->textfile, "r"))) {
+            av_log(ctx, AV_LOG_ERROR, "The textfile %s could not be opened.\n", dtext->textfile);
+            return AVERROR(EINVAL);
+        } else {
+            uint16_t read_bytes;
+            char *tbuff = av_malloc(MAX_TEXT_SIZE);
+            if (!tbuff) {
+                av_log(ctx, AV_LOG_ERROR, "Could not allocate read buffer.\n");
+                return AVERROR(ENOMEM);
+            }
+            read_bytes = fread(tbuff, sizeof(char), MAX_TEXT_SIZE-1, fp);
+            if (read_bytes > 0) {
+                tbuff[read_bytes] = 0;
+                av_free(dtext->text);
+                dtext->text = tbuff;
+            } else {
+                av_log(ctx, AV_LOG_ERROR, "The textfile %s could not be read or is empty.\n", dtext->textfile);
+                av_free(tbuff);
+                return AVERROR(EINVAL);
+            }
+            fclose(fp);
+        }
+    }
+
+    if (!dtext->text) {
+        av_log(ctx, AV_LOG_ERROR, "Either text or a valid file must be provided (=text:<text> or =textfile:<filename>)\n");
+        return AVERROR(EINVAL);
+    }
+
+    if ((err = extract_color(ctx, dtext->fgcolor_string, dtext->fgcolor))) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid foreground color: '%s'.\n", dtext->fgcolor_string);
+        return err;
+    }
+
+    if ((err = extract_color(ctx, dtext->bgcolor_string, dtext->bgcolor))) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid background color: '%s'.\n", dtext->fgcolor_string);
+        return err;
+    }
+
+    if ((err = FT_Init_FreeType(&(dtext->library)))) {
+        av_log(ctx, AV_LOG_ERROR, "Could not load FreeType: %s\n", FT_ERRMSG(err));
+        return AVERROR(EINVAL);
+    }
+
+    if ((err = FT_New_Face(dtext->library, dtext->fontfile, 0, &(dtext->face)))) {
+        av_log(ctx, AV_LOG_ERROR, "Could not load fontface %s: %s\n", dtext->fontfile, FT_ERRMSG(err));
+        return AVERROR(EINVAL);
+    }
+    if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
+        av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n", dtext->fontsize, FT_ERRMSG(err));
+        return AVERROR(EINVAL);
+    }
+
+    dtext->use_kerning = FT_HAS_KERNING(dtext->face);
+
+    /* load and cache glyphs */
+    y_max = -32000;
+    y_min =  32000;
+    /* FIXME: Supports only ASCII text now. Add Unicode support */
+    for (c=0; c <= 255; c++) {
+        /* Load char */
+        err = FT_Load_Char(dtext->face, (unsigned char)c, FT_LOAD_RENDER | FT_LOAD_MONOCHROME);
+        if (err)
+            continue;  /* ignore errors */
+
+        dtext->bitmaps    [c] = dtext->face->glyph->bitmap;
+        dtext->bitmap_left[c] = dtext->face->glyph->bitmap_left;
+        dtext->bitmap_top [c] = dtext->face->glyph->bitmap_top;
+        dtext->advance    [c] = dtext->face->glyph->advance.x >> 6;
+
+        err = FT_Get_Glyph(dtext->face->glyph, &(dtext->glyphs[c]));
+        if (err)
+            continue;  /* ignore errors */
+
+        dtext->glyphs_index[c] = FT_Get_Char_Index(dtext->face, (unsigned char)c);
+
+        /* Measure text height to calculate text_height (or the maximum text height) */
+        FT_Glyph_Get_CBox(dtext->glyphs[c], ft_glyph_bbox_pixels, &bbox);
+        if (bbox.yMax > y_max)
+          y_max = bbox.yMax;
+        if (bbox.yMin < y_min)
+          y_min = bbox.yMin;
+    }
+
+    dtext->text_height = y_max - y_min;
+    dtext->baseline = y_max;
+
+    return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    DrawTextContext *dtext = ctx->priv;
+    av_free(dtext->fontfile);
+    av_free(dtext->text);
+    av_free(dtext->textfile);
+    av_free(dtext->fgcolor_string);
+    av_free(dtext->bgcolor_string);
+    FT_Done_Face(dtext->face);
+    FT_Done_FreeType(dtext->library);
+}
+
+static int config_input(AVFilterLink *link)
+{
+    DrawTextContext *dtext = link->dst->priv;
+    const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[link->format];
+    dtext->hsub = pix_desc->log2_chroma_w;
+    dtext->vsub = pix_desc->log2_chroma_h;
+    return 0;
+}
+
+#define SET_PIXEL(picref, yuv_color, x, y, hsub, vsub) { \
+    luma_pos    = ((x)          ) + ((y)          ) * picref->linesize[0]; \
+    chroma_pos1 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[1]; \
+    chroma_pos2 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[2]; \
+    picref->data[0][luma_pos   ] = (yuv_color[3] * yuv_color[0] + (255 - yuv_color[3]) * picref->data[0][luma_pos   ]) >> 8; \
+    picref->data[1][chroma_pos1] = (yuv_color[3] * yuv_color[1] + (255 - yuv_color[3]) * picref->data[1][chroma_pos1]) >> 8; \
+    picref->data[2][chroma_pos2] = (yuv_color[3] * yuv_color[2] + (255 - yuv_color[3]) * picref->data[2][chroma_pos2]) >> 8; \
+}
+
+#define GET_PIXEL(picref, yuv_color, x, y, hsub, vsub) { \
+    yuv_color[0] = picref->data[0][( x           ) + ( y           ) * picref->linesize[0]]; \
+    yuv_color[1] = picref->data[1][((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[1]]; \
+    yuv_color[2] = picref->data[2][((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[2]]; \
+}
+
+static inline void draw_glyph(AVFilterBufferRef *picref, FT_Bitmap *bitmap, unsigned int x,
+                              unsigned int y, unsigned int width, unsigned int height,
+                              unsigned char yuv_fgcolor[4], unsigned char yuv_bgcolor[4],
+                              short int outline, int hsub, int vsub)
+{
+    int r, c;
+    unsigned int luma_pos, chroma_pos1, chroma_pos2;
+    uint8_t spixel, dpixel[4], 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 picref (destination) */
+                GET_PIXEL(picref, dpixel, c+x, y+r, hsub, vsub);
+
+                /* pixel in the glyph bitmap (source) */
+                spixel = bitmap->buffer[r*bitmap->pitch + c/8] & (0x80>>(c%8));
+
+                if (spixel)
+                    memcpy(dpixel, yuv_fgcolor, 4);
+
+                if (outline) {
+                    /* border detection: */
+                    if (!in_glyph && spixel) {
+                        /* left border detected */
+                        in_glyph = 1;
+                        /* draw left pixel border */
+                        if (c-1 >= 0)
+                            SET_PIXEL(picref, yuv_bgcolor, c+x-1, y+r, hsub, vsub);
+                    } else if (in_glyph && !spixel) {
+                    /* right border detected */
+                        in_glyph = 0;
+                        /* 'draw' right pixel border */
+                        memcpy(dpixel, yuv_bgcolor, 4);
+                    }
+
+                    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(picref, yuv_bgcolor, c+x, y+r-1, hsub, vsub);
+
+                        /* bottom border detection */
+                        if ((r+1 < height) && (!(bitmap->buffer[(r+1) * bitmap->pitch + c/8] & (0x80>>(c%8)))))
+                            /* draw bottom border */
+                            SET_PIXEL(picref, yuv_bgcolor, c+x, y+r+1, hsub, vsub);
+                    }
+                }
+                SET_PIXEL(picref, dpixel, c+x, y+r, hsub, vsub);
+            }
+        }
+    }
+}
+
+static inline void drawbox(AVFilterBufferRef *picref, unsigned int x, unsigned int y,
+                           unsigned int width, unsigned int height,
+                           unsigned char yuv_color[4], int hsub, int vsub)
+{
+    int i, plane;
+    uint8_t *p;
+
+    if (yuv_color[3] != 0xFF) {
+        unsigned int j, luma_pos, chroma_pos1, chroma_pos2;
+
+        for (j = 0; j < height; j++)
+            for (i = 0; i < width; i++)
+                SET_PIXEL(picref, yuv_color, (i+x), (y+j), hsub, vsub);
+
+    } else {
+        for (plane = 0; plane < 3 && picref->data[plane]; plane++) {
+            int hsub1 = plane == 1 || plane == 2 ? hsub : 0;
+            int vsub1 = plane == 1 || plane == 2 ? vsub : 0;
+
+            p = picref->data[plane] + (y >> vsub1) * picref->linesize[plane] + (x >> hsub1);
+            for (i = 0; i < (height >> vsub1); i++) {
+                memset(p, yuv_color[plane], (width >> hsub1));
+                p += picref->linesize[plane];
+            }
+        }
+    }
+}
+
+static void draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref, int width, int height)
+{
+    DrawTextContext *dtext = ctx->priv;
+    FT_Face face = dtext->face;
+    FT_GlyphSlot  slot = face->glyph;
+    unsigned char *text = dtext->text;
+    unsigned char c;
+    unsigned char buff[MAX_TEXT_SIZE];
+    int x = 0, y = 0, i = 0, size = 0;
+    time_t now = time(0);
+    int str_w, str_w_max;
+    FT_Vector pos[MAX_TEXT_SIZE];
+    FT_Vector delta;
+    struct tm ltime;
+
+#if HAVE_LOCALTIME_R
+    strftime(buff, sizeof(buff), text, localtime_r(&now, &ltime));
+    text = buff;
+#else
+    av_log(ctx, AV_LOG_WARNING, "strftime() expansion unavailable!");
+#endif
+    size = strlen(text);
+
+    /* measure text size and save glyphs position*/
+    str_w = str_w_max = 0;
+    x = dtext->x;
+    y = dtext->y;
+    for (i=0; i < size; i++) {
+        c = text[i];
+        /* kerning */
+        if (dtext->use_kerning && (i > 0) && dtext->glyphs_index[c]) {
+            FT_Get_Kerning(dtext->face, dtext->glyphs_index[text[i-1]],
+                           dtext->glyphs_index[c], ft_kerning_default, &delta);
+            x += delta.x >> 6;
+        }
+
+        if (((x + dtext->advance[c]) >= width) || (c == '\n')) {
+            if (c != '\n')
+                str_w_max = width - dtext->x - 1;
+            y += dtext->text_height;
+            x = dtext->x;
+        }
+
+        /* save position */
+        pos[i].x = x + dtext->bitmap_left[c];
+        pos[i].y = y - dtext->bitmap_top [c] + dtext->baseline;
+        x     += dtext->advance[c];
+        str_w += dtext->advance[c];
+    }
+    y += dtext->text_height;
+    if (str_w_max == 0)
+        str_w_max = str_w;
+    if (dtext->draw_box) {
+        /* Check if it doesn't pass the limits */
+        if (str_w_max + dtext->x >= width)
+            str_w_max = width - dtext->x - 1;
+        if (y >= height)
+            y = height - 1;
+
+        /* Draw Background */
+        drawbox(picref, dtext->x, dtext->y, str_w_max, y-dtext->y,
+                dtext->bgcolor, dtext->hsub, dtext->vsub);
+    }
+
+    /* Draw Glyphs */
+    for (i=0; i < size; i++) {
+        c = text[i];
+
+        /* skip new line char, just go to new line */
+        if (c == '\n')
+            continue;
+
+        /* now, draw to our target surface */
+        draw_glyph(picref, &(dtext->bitmaps[c]), pos[i].x, pos[i].y, width, height,
+                   dtext->fgcolor, dtext->bgcolor, dtext->outline, dtext->hsub, dtext->vsub);
+
+        /* increment pen position */
+        x += slot->advance.x >> 6;
+    }
+}
+
+static void end_frame(AVFilterLink *link)
+{
+    AVFilterLink *output = link->dst->outputs[0];
+    AVFilterBufferRef *picref = link->cur_buf;
+
+    draw_text(link->dst, picref, picref->video->w, picref->video->h);
+
+    avfilter_draw_slice(output, 0, picref->video->h, 1);
+    avfilter_end_frame(output);
+}
+
+AVFilter avfilter_vf_drawtext = {
+    .name      = "drawtext",
+    .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
+    .priv_size = sizeof(DrawTextContext),
+    .init      = init,
+    .uninit    = uninit,
+
+    .query_formats   = query_formats,
+    .inputs    = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = AVMEDIA_TYPE_VIDEO,
+                                    .get_video_buffer= avfilter_null_get_video_buffer,
+                                    .start_frame     = avfilter_null_start_frame,
+                                    .end_frame       = end_frame,
+                                    .config_props    = config_input,
+                                    .min_perms       = AV_PERM_WRITE |
+                                                       AV_PERM_READ,
+                                    .rej_perms       = AV_PERM_PRESERVE },
+                                  { .name = NULL}},
+    .outputs   = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = AVMEDIA_TYPE_VIDEO, },
+                                  { .name = NULL}},
+};
-- 
1.7.1




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