+typedef struct PtsCorrectionContext {
+ int64_t num_faulty_pts; /// Number of incorrect PTS values so far
+ int64_t num_faulty_dts; /// Number of incorrect DTS values so far
+ int64_t last_pts; /// PTS of the last frame
+ int64_t last_dts; /// DTS of the last frame
+} PtsCorrectionContext;
+
+/**
+ * Reset the state of the PtsCorrectionContext.
+ */
+void init_pts_correction(PtsCorrectionContext *ctx);
+
+/**
+ * Attempt to guess proper monotonic timestamps for decoded video frames
+ * which might have incorrect times. Input timestamps may wrap around, in
+ * which case the output will as well.
+ *
+ * @param ctx the PtsCorrectionContext carrying stream pts information
+ * @param pts the pts field of the decoded AVPacket, as passed through
+ * AVCodecContext.reordered_opaque
+ * @param dts the dts field of the decoded AVPacket
+ * @return one of the input values, may be AV_NOPTS_VALUE
+ */
+int64_t guess_correct_pts(PtsCorrectionContext *ctx, int64_t pts, int64_t dts);
+
+/**
+ * Get a file corresponding to a preset file.
+ *
+ * If is_path is non-zero, look for the file in the path preset_name.
+ * Otherwise search for a file named arg.avpreset in the directories
+ * $AVCONV_DATADIR (if set), $HOME/.avconv, and in the datadir defined
+ * at configuration time, in that order. If no such file is found and
+ * codec_name is defined, then search for a file named
+ * codec_name-preset_name.avpreset in the above-mentioned directories.
+ *
+ * @param filename buffer where the name of the found filename is written
+ * @param filename_size size in bytes of the filename buffer
+ * @param preset_name name of the preset to search
+ * @param is_path tell if preset_name is a filename path
+ * @param codec_name name of the codec for which to look for the
+ * preset, may be NULL
+ */
+FILE *get_preset_file(char *filename, size_t filename_size,
+ const char *preset_name, int is_path, const char *codec_name);
+
+/**
+ * Realloc array to hold new_size elements of elem_size.
+ * Calls exit() on failure.
+ *
+ * @param array array to reallocate
+ * @param elem_size size in bytes of each element
+ * @param size new element count will be written here
+ * @param new_size number of elements to place in reallocated array
+ * @return reallocated array
+ */
+void *grow_array(void *array, int elem_size, int *size, int new_size);
+
+/**
+ * Get a string describing a media type.
+ */
+const char *media_type_string(enum AVMediaType media_type);
+
+#define GROW_ARRAY(array, nb_elems)\
+ array = grow_array(array, sizeof(*array), &nb_elems, nb_elems + 1)
+
+#define GET_PIX_FMT_NAME(pix_fmt)\
+ const char *name = av_get_pix_fmt_name(pix_fmt);
+
+#define GET_SAMPLE_FMT_NAME(sample_fmt)\
+ const char *name = av_get_sample_fmt_name(sample_fmt)
+
+#define GET_SAMPLE_RATE_NAME(rate)\
+ char name[16];\
+ snprintf(name, sizeof(name), "%d", rate);
+
+#define GET_CH_LAYOUT_NAME(ch_layout)\
+ char name[16];\
+ snprintf(name, sizeof(name), "0x%"PRIx64, ch_layout);
+
+#define GET_CH_LAYOUT_DESC(ch_layout)\
+ char name[128];\
+ av_get_channel_layout_string(name, sizeof(name), 0, ch_layout);
+
+#endif /* LIBAV_CMDUTILS_H */