avformat/avio: Add Metacube support

[ffmpeg] / libavformat / avio.h

diff --git a/libavformat/avio.h b/libavformat/avio.h
index d022820a6edf301a06389f83f2ce01f93a3decae..bf74f2bbbe45e009314070ec9a6bb3d2cc90055e 100644 (file)
--- a/libavformat/avio.h
+++ b/libavformat/avio.h
@@ -349,6 +349,30 @@ typedef struct AVIOContext {
      * Try to buffer at least this amount of data before flushing it
      */
     int min_packet_size;
+
+    /**
+     * If set, all output will be wrapped in the Metacube format,
+     * for consumption by the Cubemap reflector. This is so that Cubemap
+     * can know what the header is, and where it is possible to start
+     * the stream (ie., from keyframes) without actually parsing and
+     * understanding the mux. Only relevant if write_flag is set.
+     *
+     * When wrapping in Metacube, s->buffer will have room for a 16-byte
+     * Metacube header while writing, which is constructed in avio_flush()
+     * before sending. This header is invisible to the calling code;
+     * e.g., it will not be counted in seeks and similar.
+     */
+    int metacube;
+
+    /**
+     * If the metacube flag is set, we need to know whether we've seen
+     * at least one sync point marker (AVIO_DATA_MARKER_SYNC_POINT),
+     * as many muxes don't send them out at all. If we haven't seen any sync
+     * point markers, we assume that all packets (in particular
+     * AVIO_DATA_MARKER_UNKNOWN) are valid sync start points.
+     * (This may not hold for all codecs in practice.)
+     */
+    int seen_sync_point;
 } AVIOContext;
 
 /**
@@ -692,6 +716,12 @@ int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen);
  */
 #define AVIO_FLAG_NONBLOCK 8
 
+/**
+ * If set, all output will be wrapped in the Metacube format.
+ * See AVIOContext::metacube for more information.
+ */
+#define AVIO_FLAG_METACUBE 16
+
 /**
  * Use direct mode.
  * avio_read and avio_write should if possible be satisfied directly