#36: libavfilter: empty source buffer + yadif filters chain, polling for frames -> assertion failed ----------------------+---------------------- Reporter: fpretto | Owner: michael Type: defect | Status: new Priority: normal | Component: avfilter Version: | Keywords: Blocked By: | Blocking: Reproduced: 0 | Analyzed: 0 ----------------------+---------------------- NB: the "nullsink" filter is used improperly as the last filter in the chain. The following self compiling sample gives: Assertion failed! Program: C:\Users\ceztko\Staging\target\Debug\Test.exe File: libavfilter/vf_yadif.c, Line 277 Expression: yadif->next Polling for frames with the empty source filter should, IMO, return 0, or be a specific switchable error (not a generic -1). {{{ #include <stdio.h> #include <libavfilter/avfilter.h> #include <libavfilter/avfiltergraph.h> #include <libavfilter/vsrc_buffer.h> int main(int argc, char* argv[]) { avfilter_register_all(); AVFilterGraph *filter_graph = avfilter_graph_alloc(); if (filter_graph == NULL) printf("error init"); AVFilter *buffer_filter = avfilter_get_by_name("buffer"); if (buffer_filter == NULL) printf("error init"); char args[256]; snprintf(args, sizeof(args), "%d:%d:%d:%d:%d:%d:%d", 720, 576, PIX_FMT_YUV420P, 1, 25, 16, 15); int rv; // Buffer video source: the decoded frames from the codec will be inserted here AVFilterContext *buffer_filter_ctx; rv = avfilter_graph_create_filter(&buffer_filter_ctx, buffer_filter, "src", args, NULL, filter_graph); if (rv != 0) printf("error init"); AVFilter *sink_filter = avfilter_get_by_name("nullsink"); if (sink_filter == NULL) printf("error init"); // Null video sink: to terminate the filter chain AVFilterContext *sink_filter_ctx; rv = avfilter_graph_create_filter(&sink_filter_ctx, sink_filter, "out", NULL, NULL, filter_graph); if (rv != 0) printf("error init"); // Endpoints for the filter graph AVFilterInOut *buffer_filter_outputs = (AVFilterInOut *)av_mallocz(sizeof(AVFilterInOut)); if (buffer_filter_outputs == NULL) printf("error init"); buffer_filter_outputs->name = av_strdup("in"); buffer_filter_outputs->filter_ctx = buffer_filter_ctx; buffer_filter_outputs->pad_idx = 0; buffer_filter_outputs->next = NULL; AVFilterInOut *sink_filter_inputs = (AVFilterInOut *)av_mallocz(sizeof(AVFilterInOut)); if (sink_filter_inputs == NULL) printf("error init"); sink_filter_inputs->name = av_strdup("out"); sink_filter_inputs->filter_ctx = sink_filter_ctx; sink_filter_inputs->pad_idx = 0; sink_filter_inputs->next = NULL; rv = avfilter_graph_parse(filter_graph, "yadif=1-1", sink_filter_inputs, buffer_filter_outputs, NULL); if (rv != 0) printf("error init"); rv = avfilter_graph_config(filter_graph, NULL); if (rv != 0) printf("error init"); AVFilterLink *output_link = sink_filter_ctx->inputs[0]; rv = avfilter_poll_frame(output_link); printf("%d", rv); return 0; } }}} -- Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/36> FFmpeg <http://ffmpeg.org> FFmpeg issue tracker