Unlike avfilter_graph_parse(), it returns unlinked inputs and outputs to the caller, which allows parsing of graphs where inputs/outputs are not known in advance.
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| @@ -91,11 +91,11 @@ void avfilter_graph_free(AVFilterGraph **graph); · 90 unmodified lines | ||
| 91 | 91 | /** |
| 92 | 92 | * A linked-list of the inputs/outputs of the filter chain. |
| 93 | 93 | * |
| 94 | − * This is mainly useful for avfilter_graph_parse(), since this | |
| 95 | − * function may accept a description of a graph with not connected | |
| 96 | − * input/output pads. This struct specifies, per each not connected | |
| 97 | − * pad contained in the graph, the filter context and the pad index | |
| 98 | − * required for establishing a link. | |
| 94 | + * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(), | |
| 95 | + * where it is used to communicate open (unlinked) inputs and outputs from and | |
| 96 | + * to the caller. | |
| 97 | + * This struct specifies, per each not connected pad contained in the graph, the | |
| 98 | + * filter context and the pad index required for establishing a link. | |
| 99 | 99 | */ |
| 100 | 100 | typedef struct AVFilterInOut { |
| 101 | 101 | /** unique name for this input/output in the list */ |
| @@ -124,4 +124,38 @@ int avfilter_graph_parse(AVFilterGraph *graph, const char *filters, · 22 unmodified lines | ||
| 124 | 124 | AVFilterInOut *inputs, AVFilterInOut *outputs, |
| 125 | 125 | void *log_ctx); |
| 126 | 126 | |
| 127 | +/** | |
| 128 | + * Add a graph described by a string to a graph. | |
| 129 | + * | |
| 130 | + * @param[in] graph the filter graph where to link the parsed graph context | |
| 131 | + * @param[in] filters string to be parsed | |
| 132 | + * @param[out] inputs a linked list of all free (unlinked) inputs of the | |
| 133 | + * parsed graph will be returned here. It is to be freed | |
| 134 | + * by the caller using avfilter_inout_free(). | |
| 135 | + * @param[out] outputs a linked list of all free (unlinked) outputs of the | |
| 136 | + * parsed graph will be returned here. It is to be freed by the | |
| 137 | + * caller using avfilter_inout_free(). | |
| 138 | + * @return zero on success, a negative AVERROR code on error | |
| 139 | + * | |
| 140 | + * @note the difference between avfilter_graph_parse2() and | |
| 141 | + * avfilter_graph_parse() is that in avfilter_graph_parse(), the caller provides | |
| 142 | + * the lists of inputs and outputs, which therefore must be known before calling | |
| 143 | + * the function. On the other hand, avfilter_graph_parse2() \em returns the | |
| 144 | + * inputs and outputs that are left unlinked after parsing the graph and the | |
| 145 | + * caller then deals with them. Another difference is that in | |
| 146 | + * avfilter_graph_parse(), the inputs parameter describes inputs of the | |
| 147 | + * <em>already existing</em> part of the graph; i.e. from the point of view of | |
| 148 | + * the newly created part, they are outputs. Similarly the outputs parameter | |
| 149 | + * describes outputs of the already existing filters, which are provided as | |
| 150 | + * inputs to the parsed filters. | |
| 151 | + * avfilter_graph_parse2() takes the opposite approach -- it makes no reference | |
| 152 | + * whatsoever to already existing parts of the graph and the inputs parameter | |
| 153 | + * will on return contain inputs of the newly parsed part of the graph. | |
| 154 | + * Analogously the outputs parameter will contain outputs of the newly created | |
| 155 | + * filters. | |
| 156 | + */ | |
| 157 | +int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters, | |
| 158 | + AVFilterInOut **inputs, | |
| 159 | + AVFilterInOut **outputs); | |
| 160 | + | |
| 127 | 161 | #endif /* AVFILTER_AVFILTERGRAPH_H */ |