lavfi/drawtext: add the reload option.

This commit is contained in:
Nicolas George 2012-12-02 19:58:39 +01:00
parent 83ddedbbf2
commit 0444733b78
2 changed files with 37 additions and 14 deletions

View File

@ -1935,6 +1935,10 @@ parameter @var{text}.
If both @var{text} and @var{textfile} are specified, an error is thrown.
@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.
@item x, 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

View File

@ -167,6 +167,7 @@ typedef struct {
AVTimecode tc; ///< timecode context
int tc24hmax; ///< 1 if timecode is wrapped to 24 hours, 0 otherwise
int frame_id;
int reload; ///< reload text file for each frame
} DrawTextContext;
#define OFFSET(x) offsetof(DrawTextContext, x)
@ -199,6 +200,7 @@ static const AVOption drawtext_options[]= {
{"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
{"r", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
{"rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
{"reload", "reload text file for each frame", OFFSET(reload), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
{"fix_bounds", "if true, check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS},
/* FT_LOAD_* flags */
@ -393,6 +395,29 @@ static int load_font(AVFilterContext *ctx)
return err;
}
static int load_textfile(AVFilterContext *ctx)
{
DrawTextContext *dtext = ctx->priv;
int err;
uint8_t *textbuf;
size_t textbuf_size;
if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
av_log(ctx, AV_LOG_ERROR,
"The text file '%s' could not be read or is empty\n",
dtext->textfile);
return err;
}
if (!(dtext->text = av_realloc(dtext->text, textbuf_size + 1)))
return AVERROR(ENOMEM);
memcpy(dtext->text, textbuf, textbuf_size);
dtext->text[textbuf_size] = 0;
av_file_unmap(textbuf, textbuf_size);
return 0;
}
static av_cold int init(AVFilterContext *ctx, const char *args)
{
int err;
@ -411,28 +436,18 @@ static av_cold int init(AVFilterContext *ctx, const char *args)
}
if (dtext->textfile) {
uint8_t *textbuf;
size_t textbuf_size;
if (dtext->text) {
av_log(ctx, AV_LOG_ERROR,
"Both text and text file provided. Please provide only one\n");
return AVERROR(EINVAL);
}
if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
av_log(ctx, AV_LOG_ERROR,
"The text file '%s' could not be read or is empty\n",
dtext->textfile);
if ((err = load_textfile(ctx)) < 0)
return err;
}
if (!(dtext->text = av_malloc(textbuf_size+1)))
return AVERROR(ENOMEM);
memcpy(dtext->text, textbuf, textbuf_size);
dtext->text[textbuf_size] = 0;
av_file_unmap(textbuf, textbuf_size);
}
if (dtext->reload && !dtext->textfile)
av_log(ctx, AV_LOG_WARNING, "No file to reload\n");
if (dtext->tc_opt_string) {
int ret = av_timecode_init_from_string(&dtext->tc, dtext->tc_rate,
dtext->tc_opt_string, ctx);
@ -972,6 +987,10 @@ static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *frame)
DrawTextContext *dtext = ctx->priv;
int ret;
if (dtext->reload)
if ((ret = load_textfile(ctx)) < 0)
return ret;
dtext->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
NAN : frame->pts * av_q2d(inlink->time_base);