Hi ffmpeg maintainers / community, New contributor here. The patch [0] for the drawtext filter was submitted some time ago now but has been reviewed yet. It seems there is no official maintainer for this filter (as per the MAINTAINERS file) What should be done to have it reviewed ?
[0] https://patchwork.ffmpeg.org/project/ffmpeg/patch/20200511143159.19390-1-da...@andreoletti.net/ Regards, David Andreoletti On Mon, May 11, 2020 2:31 PM, David Andreoletti da...@andreoletti.net wrote: drawtext allows a file to be reloaded per frame. However, the file to be reloaded is constant across frame. With textfile now supporting text expansion, a different file can be reloaded per frame. Eg: textfile=/path/fo/file{frame_num}.txt Signed-off-by: David Andreoletti <da...@andreoletti.net> --- doc/filters.texi | 16 +++++++++++++--- libavfilter/vf_drawtext.c | 19 ++++++++++++++++--- 2 files changed, 29 insertions(+), 6 deletions(-) diff --git a/doc/filters.texi b/doc/filters.texi index d19fd346ae..460d65dd88 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -9659,13 +9659,13 @@ The default value of @var{borderw} is 0. Set the color to be used for drawing border around text. For the syntax of this option, check the @ref{color syntax,,"Color" section in the ffmpeg-utils manual,ffmpeg-utils}. The default value of @var{bordercolor} is "black". @item expansion -Select how the @var{text} is expanded. Can be either @code{none}, +Select how the @var{text} and @var{textfile} are expanded. Can be either @code{none}, @code{strftime} (deprecated) or @code{normal} (default). See the @ref{drawtext_expansion, Text expansion} section below for details. @item basetime Set a start time for the count. Value is in microseconds. Only applied @@ -9786,15 +9786,19 @@ of UTF-8 encoded characters. This parameter is mandatory if no text string is specified with the parameter @var{text}. If both @var{text} and @var{textfile} are specified, an error is thrown. +This parameter supports (per frame) variable expansion. Per frame variable +expansion requires @code{reload=1}. See @var{expansion} for details. + + @item reload -If set to 1, the @var{textfile} will be reloaded before each frame. -Be sure to update it atomically, or it may be read partially, or even fail. +If set to 1, then before each frame, @var{textfile} file path will be expanded and then the file at said path will be reloaded. +Be sure to update the file atomically, or it may be read partially, or even fail. @item x @item y The expressions which specify the offsets where text will be drawn within the video frame. They are relative to the top/left border of the output image. @@ -10060,12 +10064,18 @@ drawtext="fontsize=15:fontfile=FreeSerif.ttf:text=LONG_LINE:y=h-line_h:x=-50*t" @item Show the content of file @file{CREDITS} off the bottom of the frame and scroll up. @example drawtext="fontsize=20:fontfile=FreeSerif.ttf:textfile=CREDITS:y=h-20*t" @end example +@item +Each frame, reload a different text file at /path/to/frameX.txt, where X is replaced with the frame number being processed by the filter +@example +drawtext="expansion:normal:textfile=/path/to/frame%@{frame_num@}.txt:reload=1" +@end example + @item Draw a single green letter "g", at the center of the input video. The glyph baseline is placed at half screen height. @example drawtext="fontsize=60:fontfile=FreeSerif.ttf:fontcolor=green:text=g:x=(w-max_glyph_w)/2:y=h/2-ascent" @end example diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c index abe1ca6c35..ffb1ff2330 100644 --- a/libavfilter/vf_drawtext.c +++ b/libavfilter/vf_drawtext.c @@ -152,13 +152,14 @@ typedef struct DrawTextContext { AVBPrint expanded_text; ///< used to contain the expanded text uint8_t *fontcolor_expr; ///< fontcolor expression to evaluate AVBPrint expanded_fontcolor; ///< used to contain the expanded fontcolor spec int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_* FT_Vector *positions; ///< positions for each element in the text size_t nb_positions; ///< number of elements of positions array - char *textfile; ///< file with text to be drawn + char *textfile; ///< filename with text to be drawn + AVBPrint expanded_textfile; ///< Same as textfile, except the filename can be expanded int x; ///< x position to start drawing text int y; ///< y position to start drawing text int max_glyph_w; ///< max glyph width int max_glyph_h; ///< max glyph height int shadowx, shadowy; int borderw; ///< border width @@ -565,24 +566,33 @@ static int load_font(AVFilterContext *ctx) if (!err) return 0; #endif return err; } +static int expand_text(AVFilterContext *ctx, char *text, AVBPrint *bp); static int load_textfile(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; int err; uint8_t *textbuf; uint8_t *tmp; size_t textbuf_size; - if ((err = av_file_map(s->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) { + if ((err = expand_text(ctx, s->textfile, &s->expanded_textfile)) < 0) { + av_log(ctx, AV_LOG_ERROR, "The text file path '%s' is not expandable\n", + s->textfile); + return err; + } + + av_log(ctx, AV_LOG_DEBUG, "expanded_textfile:%s\n", s->expanded_textfile.str); + + if ((err = av_file_map(s->expanded_textfile.str, &textbuf, &textbuf_size, 0, ctx)) < 0) { av_log(ctx, AV_LOG_ERROR, "The text file '%s' could not be read or is empty\n", - s->textfile); + s->expanded_textfile.str); return err; } if (textbuf_size > SIZE_MAX - 1 || !(tmp = av_realloc(s->text, textbuf_size + 1))) { av_file_unmap(textbuf, textbuf_size); return AVERROR(ENOMEM); @@ -702,12 +712,14 @@ static av_cold int init(AVFilterContext *ctx) if (!s->fontfile && !CONFIG_LIBFONTCONFIG) { av_log(ctx, AV_LOG_ERROR, "No font filename provided\n"); return AVERROR(EINVAL); } + av_bprint_init(&s->expanded_textfile, 0, AV_BPRINT_SIZE_UNLIMITED); + if (s->textfile) { if (s->text) { av_log(ctx, AV_LOG_ERROR, "Both text and text file provided. Please provide only one\n"); return AVERROR(EINVAL); } @@ -820,12 +832,13 @@ static av_cold void uninit(AVFilterContext *ctx) FT_Done_Face(s->face); FT_Stroker_Done(s->stroker); FT_Done_FreeType(s->library); av_bprint_finalize(&s->expanded_text, NULL); av_bprint_finalize(&s->expanded_fontcolor, NULL); + av_bprint_finalize(&s->expanded_textfile, NULL); } static int config_input(AVFilterLink *inlink) { AVFilterContext *ctx = inlink->dst; DrawTextContext *s = ctx->priv; -- 2.26.2 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
