[FFmpeg-soc] libavfilter audio work - qualification task
Stefano Sabatini
stefano.sabatini-lala at poste.it
Thu Apr 22 00:35:26 CEST 2010
On date Wednesday 2010-04-21 07:55:16 -0700, S.N. Hemanth Meenakshisundaram encoded:
[...]
> Also fixed alignment and style wherever non standard. Please review
> and let me know if there's anything else to be fixed. I will now
> work on fixing the corruption in vf_yadif. The complete diff for
> drawtext, documentation, Makefile/allfilters changes is attached
> below.
> Index: allfilters.c
> ===================================================================
> --- allfilters.c (revision 5734)
> +++ allfilters.c (working copy)
> @@ -37,6 +37,7 @@
> REGISTER_FILTER (ASPECT, aspect, 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 (FPS, fps, vf);
> Index: diffs/03_libavfilter_doc.diff
> ===================================================================
> --- diffs/03_libavfilter_doc.diff (revision 5734)
> +++ diffs/03_libavfilter_doc.diff (working copy)
> @@ -1,8 +1,8 @@
> -Index: doc/libavfilter.texi
> +Index: libavfilter.texi
> ===================================================================
> ---- doc/libavfilter.texi (revision 22749)
> -+++ doc/libavfilter.texi (working copy)
> -@@ -139,6 +139,20 @@
> +--- libavfilter.texi (revision 22749)
> ++++ libavfilter.texi (working copy)
> +@@ -139,6 +139,101 @@
>
> The default value of ``width'' and ``height'' is 0.
>
> @@ -14,6 +14,87 @@
> +
> +Draw a box with x:y:width:height dimensions in a chosen color.
> +
Please provide a patch against the libavfilter soc trunk, it's so hard
to read a patch of a patch.
> ++ at section drawtext
> ++
> ++Draws text string or text from specified file on top of video.
> ++
> ++It accepts the following parameters:
> ++f=<font file>:t=<text>:T=<text file>:x=<x offset>:y=<y offset>:
> ++c=<foreground color>:C=<background color>:s=<font size>:b=<draw box>:
> ++o=<draw outline>
> ++
> ++f and t are mandatory parameters.
> ++
> ++The description of the accepted parameters follows.
> ++
> ++ at table @option
> ++ at item f
> ++
> ++Specifies the font file to be used for drawing text. Path must be included.
> ++This parameter is mandatory.
> ++
> ++ at item t
> ++
> ++Specifies the text string to be drawn.
> ++This parameter is mandatory and will be used if no file with text is
> ++specified or if the file fails to open.
> ++
> ++ at item T
$var{T}, same for the other vars.
Also I'm never happy about one char variables, think at reading a
script containing such variables, that's why I prefer reasonably short
but *explicative* var names.
> ++
> ++Specifies a text file containing text to be drawn. Max size of 1024
> ++characters.
> ++
> ++ at item x, y
> ++
> ++Specify 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 ``x'' and ``y'' is 0.
$var{x} and $var{y} (yes the rest of the docs should be updated as
well).
> ++
> ++ at item s
> ++
> ++Specifies the font size to be used for drawing text.
> ++
> ++The default value of ``s'' is 16.
> ++
> ++ at item c
> ++
> ++Specifies the foreground color to be used for drawing text.
> ++Specify either as a string (e.g. black or as a hex value e.g. FF0000)
> ++
> ++The default value of ``c'' is black.
> ++
> ++ at item C
> ++
> ++Specifies the background color to be used for drawing box around text
> ++or drawing text outline based on option selected.
> ++Specify either as a string (e.g. black or as a 0xRRGGBB e.g. 0xFF0000)
> ++
> ++The default value of ``C'' is white.
> ++
> ++ at item b
> ++
> ++Specifies whether to draw a box around text using background color.
> ++Value should be either 1(enable) or 0(disable).
> ++
> ++The default value of ``b'' is 0.
> ++
> ++ at item o
> ++
> ++Specifies whether to draw an outline around text using background color.
> ++Value should be either 1(enable) or 0(disable).
> ++
> ++The default value of ``o'' is 0.
> ++
> ++ at end table
> ++ at example
> ++./ffmpeg -i in.avi -vfilters drawtext=f=FreeSerif.ttf:t=TestText
> ++ :x=100:y=50:s=24:c=Yellow:C=Red:b=1 out.avi
> ++ at end example
I generally prefer avoid to mention ff* tools at all, this is the doc
for the filter, the same syntax may be used by a different
library/app.
Also use spaces to improve poor human eye-parsing, I mean something of
the kind:
"drawtext= font=FreeSerif.ttf: text=TestText: x=100: y=50: size=24:
bgcolor=yellow: fgcolor=red : box=1"
> ++
> ++Draw 'TestText' with font FreeSerif of size 24 at (100,50), text color is yellow,
> ++background color is red, draw a box around text.
> ++
> + at section fifo
> +
> + at example
> @@ -23,7 +104,7 @@
[...]
> Index: vf_drawtext.c
> ===================================================================
> --- vf_drawtext.c (revision 0)
> +++ vf_drawtext.c (revision 0)
> @@ -0,0 +1,510 @@
> +/*
> + * copyright (c) 2010 S.N. Hemanth Meenakshisundaram
> + * Original vhook author: Gustavo Sverzut Barbieri <gsbarbieri at yahoo.com.br>
> + * Libavfilter version : S.N. Hemanth Meenakshisundaram <smeenaks at ucsd.edu>
> + *
> + * 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 libavfilter/vf_drawtext.c
"@file" alone should be enough.
> + * video filter to draw text over screen
> + */
> +
> +#define MAXSIZE_TEXT 1024
> +
> +#include "avfilter.h"
> +#include "parseutils.h"
> +#include "libavcodec/colorspace.h"
> +#include "libavutil/pixdesc.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 {
> + unsigned char *text; ///< text to be drawn
> + char *file; ///< 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 char bgcolor[3]; ///< foreground color in YUV
> + unsigned char fgcolor[3]; ///< 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;
> +
> +typedef struct {
> + const AVClass *class;
> + unsigned char *f;
> + unsigned char *t;
> + char *T;
> + char *c;
> + char *C;
> + unsigned int x;
> + unsigned int y;
> + unsigned int s;
> + short int b;
> + short int o;
> +} InParams;
I really cannot understand why two structs, also please avoid one char
variables.
> +#define OFFSET(x) offsetof(InParams, x)
> +
> +static const AVOption inparams_options[]= {
> +{"f", "set f", OFFSET(f), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
> +{"t", "set t", OFFSET(t), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
> +{"T", "set T", OFFSET(T), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
> +{"c", "set c", OFFSET(c), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
> +{"C", "set C", OFFSET(C), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
> +{"b", "set b", OFFSET(b), FF_OPT_TYPE_INT, 0, 0, 1 },
> +{"o", "set o", OFFSET(o), FF_OPT_TYPE_INT, 0, 0, 1 },
> +{"s", "set s", OFFSET(s), 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 *inparams_get_name(void *ctx)
> +{
> + return "inparams";
> +}
> +
> +static const AVClass inparams_class = {
> + "InParams",
> + inparams_get_name,
> + inparams_options
> +};
Again possibly use just one context.
> +static int query_formats(AVFilterContext *ctx)
> +{
> + /* FIXME : Supports only YUV420P now. Add support for other formats */
Simpler: "FIXME: Add support for other formats"
or skip the note altogheter.
> + 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;
> + char *err_msg;
> +} ft_errors[] =
> +#include FT_ERRORS_H
> +
> +static const char *ft_err_msg(int err)
> +{
> + const struct ft_error *fterr;
> +
> + for (fterr = ft_errors; fterr->err_msg != NULL; fterr++)
> + if (fterr->err == err)
> + return fterr->err_msg;
> +
> + return "Unknown Freetype Error";
> +}
Why not simply use
#define FT_ERRMSG(e) ft_errors[e].msg
?
> +static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
> +{
> + unsigned short int c;
> + uint8_t rgba[4];
> + uint8_t err, file_valid = 0;
> + int y_max, y_min;
> + FT_BBox bbox;
> + DrawTextContext *dtext = ctx->priv;
> + InParams *in = av_malloc(sizeof(InParams));
> +
> + in->class = &inparams_class;
> + av_opt_set_defaults2(in, 0, 0);
> + in->c = av_strdup("black");
> + in->C = av_strdup("white");
> +
> + if (av_set_options_string(in, args, "=", ":") < 0) {
> + av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
> + goto fail;
> + }
> + dtext->text = in->t;
> + dtext->file = in->T;
> + dtext->draw_box = in->b;
> + dtext->outline = in->o;
> + dtext->x = in->x;
> + dtext->y = in->y;
That wouldn't be necessary if you were using just one context.
> + if (!in->f || *(in->f) == 0) {
> + av_log(ctx, AV_LOG_ERROR, "No font file provided! (=f:filename)\n");
> + goto fail;
> + }
> +
> + if (!in->t || *(in->t) == 0) {
> + av_log(ctx, AV_LOG_ERROR, "No text provided (=t:text)\n");
> + goto fail;
> + }
> +
> + if (in->T && *(in->T) != 0) {
> + FILE *fp;
> + if (!(fp = fopen(in->T, "r"))) {
> + av_log(ctx, AV_LOG_INFO, "WARNING: The file could not be opened.\
> + Using text provided with =t switch: %s", in->T);
AV_LOG_WARNING
> + } else {
> + fclose(fp);
> + file_valid = 1;
> + }
> + }
Also why is the user supposed to provide both text and text file? Just
one should be enough, and no need to warn in that case.
> + if ((in->c) && (av_parse_color(rgba, in->c, ctx) != 0)) {
> + av_log(ctx, AV_LOG_ERROR, "Invalid foreground color: '%s'.\n", in->c);
> + goto fail;
> + }
> + dtext->fgcolor[0] = RGB_TO_Y(rgba[0], rgba[1], rgba[2]);
> + dtext->fgcolor[1] = RGB_TO_U(rgba[0], rgba[1], rgba[2], 0);
> + dtext->fgcolor[2] = RGB_TO_V(rgba[0], rgba[1], rgba[2], 0);
****1****
> + if ((in->C) && (av_parse_color(rgba, in->C, ctx) != 0)) {
> + av_log(ctx, AV_LOG_ERROR, "Invalid background color: '%s'.\n", in->C);
> + goto fail;
> + }
> +
> + dtext->bgcolor[0] = RGB_TO_Y(rgba[0], rgba[1], rgba[2]);
> + dtext->bgcolor[1] = RGB_TO_U(rgba[0], rgba[1], rgba[2], 0);
> + dtext->bgcolor[2] = RGB_TO_V(rgba[0], rgba[1], rgba[2], 0);
****2****
This may be factorized.
> +
> + if ((err = FT_Init_FreeType(&(dtext->library))) != 0) {
!= is not necessary.
> + av_log(ctx, AV_LOG_ERROR, "Could not load FreeType (%s).\n", ft_err_msg(err));
> + goto fail;
> + }
> +
> + if ((err = FT_New_Face( dtext->library, in->f, 0, &(dtext->face) )) != 0) {
> + av_log(ctx, AV_LOG_ERROR, "Could not load face: %s (%s).\n", in->f, ft_err_msg(err));
> + goto fail;
> + }
> + if ((err = FT_Set_Pixel_Sizes( dtext->face, 0, in->s)) != 0) {
> + av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels (%s).\n", in->s, ft_err_msg(err));
> + goto fail;
> + }
> +
> + 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++) {
> +
> + if (!file_valid && !strrchr(dtext->text,(unsigned char)c))
> + continue;
> +
> + /* 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;
> +
> +fail:
> + av_free(in->f);
> + av_free(in->c);
> + av_free(in->C);
> + return AVERROR(EINVAL);
> +}
> +
> +static av_cold void uninit(AVFilterContext *ctx)
> +{
> + DrawTextContext *dtext = ctx->priv;
> + av_freep(&dtext->text);
> + av_freep(&dtext->file);
> + 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(pic_ref, yuv_color, x, y, hsub, vsub) { \
> + pic_ref->data[0][ (x) + (y)*pic_ref->linesize[0] ] = yuv_color[0]; \
Can be vertically aligned like:
pic_ref->data[0][ x + y *pic_ref->linesize[0] ] = yuv_color[0]; \
Same below.
> + pic_ref->data[1][ ((x >> hsub) + (y >> vsub)*pic_ref->linesize[1]) ] = yuv_color[1]; \
> + pic_ref->data[2][ ((x >> hsub) + (y >> vsub)*pic_ref->linesize[2]) ] = yuv_color[2]; \
> +}
> +
> +#define GET_PIXEL(pic_ref, yuv_color, x, y, hsub, vsub) { \
> + yuv_color[0] = pic_ref->data[0][ (x) + (y)*pic_ref->linesize[0] ]; \
> + yuv_color[1] = pic_ref->data[1][ (x >> hsub) + (y >> vsub)*pic_ref->linesize[1] ]; \
> + yuv_color[2] = pic_ref->data[2][ (x >> hsub) + (y >> vsub)*pic_ref->linesize[2] ]; \
> +}
> +
> +static inline void draw_glyph(AVFilterPicRef *pic_ref, FT_Bitmap *bitmap, unsigned int x,
> + unsigned int y, unsigned int width, unsigned int height,
> + unsigned char yuv_fgcolor[3], unsigned char yuv_color[3],
> + short int outline, int hsub, int vsub)
> +{
> + int r, c;
> + uint8_t spixel, dpixel[3], in_glyph=0;
> +
> + if (bitmap->pixel_mode == ft_pixel_mode_mono) {
> + in_glyph = 0;
> + for (r=0; (r < bitmap->rows) && (r+y < height); r++) {
> + for (c=0; (c < bitmap->width) && (c+x < width); c++) {
> + /* pixel in the pic_ref (destination) */
> + GET_PIXEL(pic_ref, 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, 3);
> +
> + if (outline) {
> + /* border detection: */
> + if ( !in_glyph && spixel ) {
> + /* left border detected */
> + in_glyph = 1;
> + /* draw left pixel border */
> + if (c-1 >= 0)
> + SET_PIXEL(pic_ref, yuv_color, (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_color, 3);
> + }
> +
> + 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(pic_ref, yuv_color, (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(pic_ref, yuv_color, (c+x), (y+r+1), hsub, vsub);
> + }
> + }
> + SET_PIXEL(pic_ref, dpixel, (c+x), (y+r), hsub, vsub);
> + }
> + }
> + }
> +}
> +
> +static inline void drawbox(AVFilterPicRef *pic_ref, unsigned int x, unsigned int y,
> + unsigned int width, unsigned int height, unsigned char yuv_color[3], int hsub, int vsub)
Long line, weird indent.
> +{
> + int i, plane;
> + uint8_t *p;
> +
> + for (plane = 0; plane < 3 && pic_ref->data[plane]; plane++) {
> + int hsub1 = plane == 1 || plane == 2 ? hsub : 0;
> + int vsub1 = plane == 1 || plane == 2 ? vsub : 0;
> +
> + p = pic_ref->data[plane] + (y >> vsub1) * pic_ref->linesize[plane] + (x >> hsub1);
> + for (i = 0; i < (height >> vsub1); i++) {
> + memset(p, yuv_color[plane], (width >> hsub1));
> + p += pic_ref->linesize[plane];
> + }
> + }
> +}
Is there is some problem at supporting alpha channel here?
> +static void draw_text(AVFilterContext *ctx, AVFilterPicRef *pic_ref, int width, int height)
> +{
> + DrawTextContext *dtext = ctx->priv;
> + FT_Face face = dtext->face;
> + FT_GlyphSlot slot = face->glyph;
> + FILE *fd = NULL;
> + unsigned char *text = dtext->text;
> + unsigned char c;
> + int x = 0, y = 0, i = 0, size = 0;
> + unsigned char buff[MAXSIZE_TEXT];
> + unsigned char tbuff[MAXSIZE_TEXT];
> + time_t now = time(0);
> + int str_w, str_w_max;
> + FT_Vector pos[MAXSIZE_TEXT];
> + FT_Vector delta;
> +
> + if (dtext->file) {
> + if (!(fd = fopen(dtext->file, "r"))) {
> + text = dtext->text;
> + av_log(ctx, AV_LOG_INFO, "WARNING: The file could not be opened.\
> + Using text provided with -t switch");
> + } else {
> + int l = fread(tbuff, sizeof(char), MAXSIZE_TEXT-1, fd);
> + if (l >= 0) {
> + tbuff[l] = 0;
> + text = tbuff;
> + } else {
> + text = dtext->text;
> + av_log(ctx, AV_LOG_INFO, "WARNING: The file could not be read.\
> + Using text provided with -t switch");
> + }
> + fclose(fd);
> + }
> + } else {
> + text = dtext->text;
> + }
Uh, what's the point of reading every time the file, and not just once
at the init stage?
> + strftime(buff, sizeof(buff), text, localtime(&now));
> + text = buff;
> + size = strlen(text);
Please document this behavior in the user docs.
Also localtime is deprecated and shouldn't be used, from GNU libc
manual:
| Using the `localtime' function is a big problem in multi-threaded
|programs. The result is returned in a static buffer and this is used in
|all threads. POSIX.1c introduced a variant of this function.
> + /* measure string 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;
> +
> + av_log(ctx, AV_LOG_ERROR, "Entry : %d, %d \n", y, dtext->text_height);
AV_LOG_DEBUG
> + /* Draw Background */
> + drawbox( pic_ref, 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 '_' (consider as space) if text was specified in cmd line and
> + * skip new line char, just go to new line */
> + if (( (c == '_') && (text == dtext->text) ) || ( c == '\n' ) )
> + continue;
> +
> + /* now, draw to our target surface */
> + draw_glyph( pic_ref,
> + &(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];
> + AVFilterPicRef *pic_ref = link->cur_pic;
> +
> + draw_text(link->dst, pic_ref, pic_ref->w, pic_ref->h);
> +
> + avfilter_draw_slice(output, 0, pic_ref->h, 1);
> + avfilter_end_frame(output);
> +}
> +
> +AVFilter avfilter_vf_drawtext = {
> + .name = "drawtext",
> + .description = "Draw text on top of video frames, requires libfreetype library.",
I'd prefer "using libfreetype" rather than "requires 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}},
> +};
Regards.
More information about the FFmpeg-soc
mailing list