Allow sniffers to return a packet of opaque data that the corresponding extractor can take advantage of to not duplicate work already done sniffing. The mp3 extractor takes advantage of this now.

Change-Id: Icb77ae3ee95a69c7da25b4d3b8696c0a2d33028a
related-to-bug: 2948754

1 files changed, 7 insertions, 2 deletions

diff --git a/include/media/stagefright/DataSource.h b/include/media/stagefright/DataSource.h
index 6f7dc38..9d2cff6 100644
--- a/include/media/stagefright/DataSource.h
+++ b/include/media/stagefright/DataSource.h
@@ -28,6 +28,7 @@
 
 namespace android {
 
+struct AMessage;
 class String8;
 
 class DataSource : public RefBase {
@@ -59,10 +60,14 @@ public:
 
     ////////////////////////////////////////////////////////////////////////////
 
-    bool sniff(String8 *mimeType, float *confidence);
+    bool sniff(String8 *mimeType, float *confidence, sp<AMessage> *meta);
 
+    // The sniffer can optionally fill in "meta" with an AMessage containing
+    // a dictionary of values that helps the corresponding extractor initialize
+    // its state without duplicating effort already exerted by the sniffer.
     typedef bool (*SnifferFunc)(
-            const sp<DataSource> &source, String8 *mimeType, float *confidence);
+            const sp<DataSource> &source, String8 *mimeType,
+            float *confidence, sp<AMessage> *meta);
 
     static void RegisterSniffer(SnifferFunc func);
     static void RegisterDefaultSniffers();