static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
{
int i, j;
int scaler_count = 0;
char inst_name[30];
/* ask all the sub-filters for their supported colorspaces */
for(i = 0; i < graph->filter_count; i ++) {
if(graph->filters[i]->filter->query_formats)
graph->filters[i]->filter->query_formats(graph->filters[i]);
else
avfilter_default_query_formats(graph->filters[i]);
}
/* go through and merge as many format lists as possible */
for(i = 0; i < graph->filter_count; i ++) {
AVFilterContext *filter = graph->filters[i];
for(j = 0; j < filter->input_count; j ++) {
AVFilterLink *link = filter->inputs[j];
if(link && link->in_formats != link->out_formats) {
if(!avfilter_merge_formats(link->in_formats,
link->out_formats)) {
AVFilterContext *scale;
char scale_args[256];
/* couldn't merge format lists. auto-insert scale filter */
snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
scaler_count++);
scale =
avfilter_open(avfilter_get_by_name("scale"),inst_name);
snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts);
if(!scale || scale->filter->init(scale, scale_args, NULL) ||
avfilter_insert_filter(link, scale, 0, 0)) {
avfilter_destroy(scale);
return -1;
}
if (avfilter_graph_add_filter(graph, scale) < 0)
return -1;
scale->filter->query_formats(scale);
if (((link = scale-> inputs[0]) &&
!avfilter_merge_formats(link->in_formats, link->out_formats)) ||
((link = scale->outputs[0]) &&
!avfilter_merge_formats(link->in_formats, link->out_formats))) {
av_log(log_ctx, AV_LOG_ERROR,
"Impossible to convert between the formats supported by the filter "
"'%s' and the filter '%s'\n", link->src->name, link->dst->name);
return -1;
}
}
}
}
}
return 0;
}
/**
* Create an instance of a filter, initialize and insert it in the
* filtergraph in *ctx.
*
* @param ctx the filtergraph context
* @param put here a filter context in case of successful creation and configuration, NULL otherwise.
* @param index an index which is supposed to be unique for each filter instance added to the filtergraph
* @param filt_name the name of the filter to create
* @param args the arguments provided to the filter during its initialization
* @param log_ctx the log context to use
* @return 0 in case of success, a negative AVERROR code otherwise
*/
static int create_filter(AVFilterContext **filt_ctx, AVFilterGraph *ctx, int index,
const char *filt_name, const char *args, void *log_ctx)
{
AVFilter *filt;
char inst_name[30];
char tmp_args[256];
int ret;
snprintf(inst_name, sizeof(inst_name), "Parsed filter %d %s", index, filt_name);
filt = avfilter_get_by_name(filt_name);
if (!filt) {
av_log(log_ctx, AV_LOG_ERROR,
"No such filter: '%s'\n", filt_name);
return AVERROR(EINVAL);
}
ret = avfilter_open(filt_ctx, filt, inst_name);
if (!*filt_ctx) {
av_log(log_ctx, AV_LOG_ERROR,
"Error creating filter '%s'\n", filt_name);
return ret;
}
if ((ret = avfilter_graph_add_filter(ctx, *filt_ctx)) < 0) {
avfilter_free(*filt_ctx);
return ret;
}
if (!strcmp(filt_name, "scale") && args && !strstr(args, "flags") &&
ctx->scale_sws_opts) {
snprintf(tmp_args, sizeof(tmp_args), "%s:%s",
args, ctx->scale_sws_opts);
args = tmp_args;
}
if ((ret = avfilter_init_filter(*filt_ctx, args, NULL)) < 0) {
av_log(log_ctx, AV_LOG_ERROR,
"Error initializing filter '%s' with args '%s'\n", filt_name, args);
return ret;
}
return 0;
}
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
const char *name, const char *args, void *opaque,
AVFilterGraph *graph_ctx)
{
int ret;
if ((ret = avfilter_open(filt_ctx, filt, name)) < 0)
goto fail;
if ((ret = avfilter_init_filter(*filt_ctx, args, opaque)) < 0)
goto fail;
if ((ret = avfilter_graph_add_filter(graph_ctx, *filt_ctx)) < 0)
goto fail;
return 0;
fail:
if (*filt_ctx)
avfilter_free(*filt_ctx);
*filt_ctx = NULL;
return ret;
}
