You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

225 lines
8.8KB

  1. /*
  2. * Filter graphs
  3. * copyright (c) 2007 Bobby Bingham
  4. *
  5. * This file is part of FFmpeg.
  6. *
  7. * FFmpeg is free software; you can redistribute it and/or
  8. * modify it under the terms of the GNU Lesser General Public
  9. * License as published by the Free Software Foundation; either
  10. * version 2.1 of the License, or (at your option) any later version.
  11. *
  12. * FFmpeg is distributed in the hope that it will be useful,
  13. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15. * Lesser General Public License for more details.
  16. *
  17. * You should have received a copy of the GNU Lesser General Public
  18. * License along with FFmpeg; if not, write to the Free Software
  19. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20. */
  21. #ifndef AVFILTER_AVFILTERGRAPH_H
  22. #define AVFILTER_AVFILTERGRAPH_H
  23. #include "avfilter.h"
  24. #include "libavutil/log.h"
  25. typedef struct AVFilterGraph {
  26. #if FF_API_GRAPH_AVCLASS
  27. const AVClass *av_class;
  28. #endif
  29. unsigned filter_count;
  30. AVFilterContext **filters;
  31. char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters
  32. } AVFilterGraph;
  33. /**
  34. * Allocate a filter graph.
  35. */
  36. AVFilterGraph *avfilter_graph_alloc(void);
  37. /**
  38. * Get a filter instance with name name from graph.
  39. *
  40. * @return the pointer to the found filter instance or NULL if it
  41. * cannot be found.
  42. */
  43. AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name);
  44. /**
  45. * Add an existing filter instance to a filter graph.
  46. *
  47. * @param graphctx the filter graph
  48. * @param filter the filter to be added
  49. */
  50. int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter);
  51. /**
  52. * Create and add a filter instance into an existing graph.
  53. * The filter instance is created from the filter filt and inited
  54. * with the parameters args and opaque.
  55. *
  56. * In case of success put in *filt_ctx the pointer to the created
  57. * filter instance, otherwise set *filt_ctx to NULL.
  58. *
  59. * @param name the instance name to give to the created filter instance
  60. * @param graph_ctx the filter graph
  61. * @return a negative AVERROR error code in case of failure, a non
  62. * negative value otherwise
  63. */
  64. int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
  65. const char *name, const char *args, void *opaque,
  66. AVFilterGraph *graph_ctx);
  67. /**
  68. * Check validity and configure all the links and formats in the graph.
  69. *
  70. * @param graphctx the filter graph
  71. * @param log_ctx context used for logging
  72. * @return 0 in case of success, a negative AVERROR code otherwise
  73. */
  74. int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx);
  75. /**
  76. * Free a graph, destroy its links, and set *graph to NULL.
  77. * If *graph is NULL, do nothing.
  78. */
  79. void avfilter_graph_free(AVFilterGraph **graph);
  80. /**
  81. * A linked-list of the inputs/outputs of the filter chain.
  82. *
  83. * This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(),
  84. * where it is used to communicate open (unlinked) inputs and outputs from and
  85. * to the caller.
  86. * This struct specifies, per each not connected pad contained in the graph, the
  87. * filter context and the pad index required for establishing a link.
  88. */
  89. typedef struct AVFilterInOut {
  90. /** unique name for this input/output in the list */
  91. char *name;
  92. /** filter context associated to this input/output */
  93. AVFilterContext *filter_ctx;
  94. /** index of the filt_ctx pad to use for linking */
  95. int pad_idx;
  96. /** next input/input in the list, NULL if this is the last */
  97. struct AVFilterInOut *next;
  98. } AVFilterInOut;
  99. /**
  100. * Allocate a single AVFilterInOut entry.
  101. * Must be freed with avfilter_inout_free().
  102. * @return allocated AVFilterInOut on success, NULL on failure.
  103. */
  104. AVFilterInOut *avfilter_inout_alloc(void);
  105. /**
  106. * Free the supplied list of AVFilterInOut and set *inout to NULL.
  107. * If *inout is NULL, do nothing.
  108. */
  109. void avfilter_inout_free(AVFilterInOut **inout);
  110. /**
  111. * Add a graph described by a string to a graph.
  112. *
  113. * @param graph the filter graph where to link the parsed graph context
  114. * @param filters string to be parsed
  115. * @param inputs pointer to a linked list to the inputs of the graph, may be NULL.
  116. * If non-NULL, *inputs is updated to contain the list of open inputs
  117. * after the parsing, should be freed with avfilter_inout_free().
  118. * @param outputs pointer to a linked list to the outputs of the graph, may be NULL.
  119. * If non-NULL, *outputs is updated to contain the list of open outputs
  120. * after the parsing, should be freed with avfilter_inout_free().
  121. * @return non negative on success, a negative AVERROR code on error
  122. */
  123. int avfilter_graph_parse(AVFilterGraph *graph, const char *filters,
  124. AVFilterInOut **inputs, AVFilterInOut **outputs,
  125. void *log_ctx);
  126. /**
  127. * Add a graph described by a string to a graph.
  128. *
  129. * @param[in] graph the filter graph where to link the parsed graph context
  130. * @param[in] filters string to be parsed
  131. * @param[out] inputs a linked list of all free (unlinked) inputs of the
  132. * parsed graph will be returned here. It is to be freed
  133. * by the caller using avfilter_inout_free().
  134. * @param[out] outputs a linked list of all free (unlinked) outputs of the
  135. * parsed graph will be returned here. It is to be freed by the
  136. * caller using avfilter_inout_free().
  137. * @return zero on success, a negative AVERROR code on error
  138. *
  139. * @note the difference between avfilter_graph_parse2() and
  140. * avfilter_graph_parse() is that in avfilter_graph_parse(), the caller provides
  141. * the lists of inputs and outputs, which therefore must be known before calling
  142. * the function. On the other hand, avfilter_graph_parse2() \em returns the
  143. * inputs and outputs that are left unlinked after parsing the graph and the
  144. * caller then deals with them. Another difference is that in
  145. * avfilter_graph_parse(), the inputs parameter describes inputs of the
  146. * <em>already existing</em> part of the graph; i.e. from the point of view of
  147. * the newly created part, they are outputs. Similarly the outputs parameter
  148. * describes outputs of the already existing filters, which are provided as
  149. * inputs to the parsed filters.
  150. * avfilter_graph_parse2() takes the opposite approach -- it makes no reference
  151. * whatsoever to already existing parts of the graph and the inputs parameter
  152. * will on return contain inputs of the newly parsed part of the graph.
  153. * Analogously the outputs parameter will contain outputs of the newly created
  154. * filters.
  155. */
  156. int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters,
  157. AVFilterInOut **inputs,
  158. AVFilterInOut **outputs);
  159. /**
  160. * Send a command to one or more filter instances.
  161. *
  162. * @param graph the filter graph
  163. * @param target the filter(s) to which the command should be sent
  164. * "all" sends to all filters
  165. * otherwise it can be a filter or filter instance name
  166. * which will send the command to all matching filters.
  167. * @param cmd the command to sent, for handling simplicity all commands must be alphanumeric only
  168. * @param arg the argument for the command
  169. * @param res a buffer with size res_size where the filter(s) can return a response.
  170. *
  171. * @returns >=0 on success otherwise an error code.
  172. * AVERROR(ENOSYS) on unsupported commands
  173. */
  174. int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags);
  175. /**
  176. * Queue a command for one or more filter instances.
  177. *
  178. * @param graph the filter graph
  179. * @param target the filter(s) to which the command should be sent
  180. * "all" sends to all filters
  181. * otherwise it can be a filter or filter instance name
  182. * which will send the command to all matching filters.
  183. * @param cmd the command to sent, for handling simplicity all commands must be alphanummeric only
  184. * @param arg the argument for the command
  185. * @param ts time at which the command should be sent to the filter
  186. *
  187. * @note As this executes commands after this function returns, no return code
  188. * from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported.
  189. */
  190. int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts);
  191. /**
  192. * Dump a graph into a human-readable string representation.
  193. *
  194. * @param graph the graph to dump
  195. * @param options formatting options; currently ignored
  196. * @return a string, or NULL in case of memory allocation failure;
  197. * the string must be freed using av_free
  198. */
  199. char *avfilter_graph_dump(AVFilterGraph *graph, const char *options);
  200. #endif /* AVFILTER_AVFILTERGRAPH_H */