+ output_packet(of, &opkt, ost);
+}
+
+static int ifilter_send_frame(InputFilter *ifilter, AVFrame *frame)
+{
+ FilterGraph *fg = ifilter->graph;
+ int need_reinit, ret, i;
+
+ /* determine if the parameters for this input changed */
+ need_reinit = ifilter->format != frame->format;
+ if (!!ifilter->hw_frames_ctx != !!frame->hw_frames_ctx ||
+ (ifilter->hw_frames_ctx && ifilter->hw_frames_ctx->data != frame->hw_frames_ctx->data))
+ need_reinit = 1;
+
+ switch (ifilter->ist->st->codecpar->codec_type) {
+ case AVMEDIA_TYPE_AUDIO:
+ need_reinit |= ifilter->sample_rate != frame->sample_rate ||
+ ifilter->channel_layout != frame->channel_layout;
+ break;
+ case AVMEDIA_TYPE_VIDEO:
+ need_reinit |= ifilter->width != frame->width ||
+ ifilter->height != frame->height;
+ break;
+ }
+
+ if (need_reinit) {
+ ret = ifilter_parameters_from_frame(ifilter, frame);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* (re)init the graph if possible, otherwise buffer the frame and return */
+ if (need_reinit || !fg->graph) {
+ for (i = 0; i < fg->nb_inputs; i++) {
+ if (fg->inputs[i]->format < 0) {
+ AVFrame *tmp = av_frame_clone(frame);
+ if (!tmp)
+ return AVERROR(ENOMEM);
+ av_frame_unref(frame);
+
+ if (!av_fifo_space(ifilter->frame_queue)) {
+ ret = av_fifo_realloc2(ifilter->frame_queue, 2 * av_fifo_size(ifilter->frame_queue));
+ if (ret < 0)
+ return ret;
+ }
+ av_fifo_generic_write(ifilter->frame_queue, &tmp, sizeof(tmp), NULL);
+ return 0;
+ }
+ }
+
+ ret = poll_filters();
+ if (ret < 0 && ret != AVERROR_EOF) {
+ char errbuf[128];
+ av_strerror(ret, errbuf, sizeof(errbuf));
+
+ av_log(NULL, AV_LOG_ERROR, "Error while filtering: %s\n", errbuf);
+ return ret;
+ }
+
+ ret = configure_filtergraph(fg);
+ if (ret < 0) {
+ av_log(NULL, AV_LOG_ERROR, "Error reinitializing filters!\n");
+ return ret;
+ }
+ }
+
+ ret = av_buffersrc_add_frame(ifilter->filter, frame);
+ if (ret < 0) {
+ av_log(NULL, AV_LOG_ERROR, "Error while filtering\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ifilter_send_eof(InputFilter *ifilter)
+{
+ int i, j, ret;
+
+ ifilter->eof = 1;
+
+ if (ifilter->filter) {
+ ret = av_buffersrc_add_frame(ifilter->filter, NULL);
+ if (ret < 0)
+ return ret;
+ } else {
+ // the filtergraph was never configured
+ FilterGraph *fg = ifilter->graph;
+ for (i = 0; i < fg->nb_inputs; i++)
+ if (!fg->inputs[i]->eof)
+ break;
+ if (i == fg->nb_inputs) {
+ // All the input streams have finished without the filtergraph
+ // ever being configured.
+ // Mark the output streams as finished.
+ for (j = 0; j < fg->nb_outputs; j++)
+ finish_output_stream(fg->outputs[j]->ost);
+ }
+ }
+
+ return 0;
+}
+
+// This does not quite work like avcodec_decode_audio4/avcodec_decode_video2.
+// There is the following difference: if you got a frame, you must call
+// it again with pkt=NULL. pkt==NULL is treated differently from pkt.size==0
+// (pkt==NULL means get more output, pkt.size==0 is a flush/drain packet)
+static int decode(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *pkt)
+{
+ int ret;
+
+ *got_frame = 0;
+
+ if (pkt) {
+ ret = avcodec_send_packet(avctx, pkt);
+ // In particular, we don't expect AVERROR(EAGAIN), because we read all
+ // decoded frames with avcodec_receive_frame() until done.
+ if (ret < 0)
+ return ret == AVERROR_EOF ? 0 : ret;
+ }
+
+ ret = avcodec_receive_frame(avctx, frame);
+ if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF)
+ return ret;
+ if (ret >= 0)
+ *got_frame = 1;
+
+ return 0;