am b8814dce: Merge "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." into gingerbread

Merge commit 'b8814dce287552c1bdf13fa999296ebc7387776d' into gingerbread-plus-aosp

* commit 'b8814dce287552c1bdf13fa999296ebc7387776d':
  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.
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 @@
 
     ////////////////////////////////////////////////////////////////////////////
 
-    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();
diff --git a/media/libstagefright/AMRExtractor.cpp b/media/libstagefright/AMRExtractor.cpp
index 70af2da..1b05528 100644
--- a/media/libstagefright/AMRExtractor.cpp
+++ b/media/libstagefright/AMRExtractor.cpp
@@ -87,7 +87,7 @@
       mInitCheck(NO_INIT) {
     String8 mimeType;
     float confidence;
-    if (!SniffAMR(mDataSource, &mimeType, &confidence)) {
+    if (!SniffAMR(mDataSource, &mimeType, &confidence, NULL)) {
         return;
     }
 
@@ -276,7 +276,8 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 bool SniffAMR(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *) {
     char header[9];
 
     if (source->readAt(0, header, sizeof(header)) != sizeof(header)) {
diff --git a/media/libstagefright/DataSource.cpp b/media/libstagefright/DataSource.cpp
index 90a596c..49eac62 100644
--- a/media/libstagefright/DataSource.cpp
+++ b/media/libstagefright/DataSource.cpp
@@ -25,6 +25,7 @@
 
 #include "matroska/MatroskaExtractor.h"
 
+#include <media/stagefright/foundation/AMessage.h>
 #include <media/stagefright/DataSource.h>
 #include <media/stagefright/FileSource.h>
 #include <media/stagefright/MediaErrors.h>
@@ -56,19 +57,23 @@
 Mutex DataSource::gSnifferMutex;
 List<DataSource::SnifferFunc> DataSource::gSniffers;
 
-bool DataSource::sniff(String8 *mimeType, float *confidence) {
+bool DataSource::sniff(
+        String8 *mimeType, float *confidence, sp<AMessage> *meta) {
     *mimeType = "";
     *confidence = 0.0f;
+    meta->clear();
 
     Mutex::Autolock autoLock(gSnifferMutex);
     for (List<SnifferFunc>::iterator it = gSniffers.begin();
          it != gSniffers.end(); ++it) {
         String8 newMimeType;
         float newConfidence;
-        if ((*it)(this, &newMimeType, &newConfidence)) {
+        sp<AMessage> newMeta;
+        if ((*it)(this, &newMimeType, &newConfidence, &newMeta)) {
             if (newConfidence > *confidence) {
                 *mimeType = newMimeType;
                 *confidence = newConfidence;
+                *meta = newMeta;
             }
         }
     }
@@ -92,13 +97,13 @@
 
 // static
 void DataSource::RegisterDefaultSniffers() {
-    RegisterSniffer(SniffMP3);
     RegisterSniffer(SniffMPEG4);
-    RegisterSniffer(SniffAMR);
-    RegisterSniffer(SniffWAV);
-    RegisterSniffer(SniffOgg);
     RegisterSniffer(SniffMatroska);
+    RegisterSniffer(SniffOgg);
+    RegisterSniffer(SniffWAV);
+    RegisterSniffer(SniffAMR);
     RegisterSniffer(SniffMPEG2TS);
+    RegisterSniffer(SniffMP3);
 }
 
 // static
diff --git a/media/libstagefright/MP3Extractor.cpp b/media/libstagefright/MP3Extractor.cpp
index 4058fbc..2e36968 100644
--- a/media/libstagefright/MP3Extractor.cpp
+++ b/media/libstagefright/MP3Extractor.cpp
@@ -22,6 +22,7 @@
 
 #include "include/ID3.h"
 
+#include <media/stagefright/foundation/AMessage.h>
 #include <media/stagefright/DataSource.h>
 #include <media/stagefright/MediaBuffer.h>
 #include <media/stagefright/MediaBufferGroup.h>
@@ -456,15 +457,31 @@
     MP3Source &operator=(const MP3Source &);
 };
 
-MP3Extractor::MP3Extractor(const sp<DataSource> &source)
+MP3Extractor::MP3Extractor(
+        const sp<DataSource> &source, const sp<AMessage> &meta)
     : mDataSource(source),
       mFirstFramePos(-1),
       mFixedHeader(0),
       mByteNumber(0) {
     off_t pos = 0;
     uint32_t header;
-    bool success = Resync(mDataSource, 0, &pos, &header);
-    CHECK(success);
+    bool success;
+
+    int64_t meta_offset;
+    uint32_t meta_header;
+    if (meta != NULL
+            && meta->findInt64("offset", &meta_offset)
+            && meta->findInt32("header", (int32_t *)&meta_header)) {
+        // The sniffer has already done all the hard work for us, simply
+        // accept its judgement.
+        pos = (off_t)meta_offset;
+        header = meta_header;
+
+        success = true;
+    } else {
+        success = Resync(mDataSource, 0, &pos, &header);
+        CHECK(success);
+    }
 
     if (success) {
         mFirstFramePos = pos;
@@ -759,15 +776,20 @@
 }
 
 bool SniffMP3(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType,
+        float *confidence, sp<AMessage> *meta) {
     off_t pos = 0;
     uint32_t header;
     if (!Resync(source, 0, &pos, &header)) {
         return false;
     }
 
+    *meta = new AMessage;
+    (*meta)->setInt64("offset", pos);
+    (*meta)->setInt32("header", header);
+
     *mimeType = MEDIA_MIMETYPE_AUDIO_MPEG;
-    *confidence = 0.3f;
+    *confidence = 0.2f;
 
     return true;
 }
diff --git a/media/libstagefright/MPEG4Extractor.cpp b/media/libstagefright/MPEG4Extractor.cpp
index 12a1e6e..ba90407 100644
--- a/media/libstagefright/MPEG4Extractor.cpp
+++ b/media/libstagefright/MPEG4Extractor.cpp
@@ -1738,7 +1738,7 @@
         || !memcmp(header, "ftypM4A ", 8) || !memcmp(header, "ftypf4v ", 8)
         || !memcmp(header, "ftypkddi", 8) || !memcmp(header, "ftypM4VP", 8)) {
         *mimeType = MEDIA_MIMETYPE_CONTAINER_MPEG4;
-        *confidence = 0.1;
+        *confidence = 0.4;
 
         return true;
     }
@@ -1805,13 +1805,14 @@
     }
 
     *mimeType = MEDIA_MIMETYPE_CONTAINER_MPEG4;
-    *confidence = 0.3f;
+    *confidence = 0.4f;
 
     return true;
 }
 
 bool SniffMPEG4(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *) {
     if (BetterSniffMPEG4(source, mimeType, confidence)) {
         return true;
     }
diff --git a/media/libstagefright/MediaExtractor.cpp b/media/libstagefright/MediaExtractor.cpp
index 56e6136..9bc94de 100644
--- a/media/libstagefright/MediaExtractor.cpp
+++ b/media/libstagefright/MediaExtractor.cpp
@@ -27,6 +27,7 @@
 
 #include "matroska/MatroskaExtractor.h"
 
+#include <media/stagefright/foundation/AMessage.h>
 #include <media/stagefright/DataSource.h>
 #include <media/stagefright/MediaDefs.h>
 #include <media/stagefright/MediaExtractor.h>
@@ -46,10 +47,12 @@
 // static
 sp<MediaExtractor> MediaExtractor::Create(
         const sp<DataSource> &source, const char *mime) {
+    sp<AMessage> meta;
+
     String8 tmp;
     if (mime == NULL) {
         float confidence;
-        if (!source->sniff(&tmp, &confidence)) {
+        if (!source->sniff(&tmp, &confidence, &meta)) {
             LOGV("FAILED to autodetect media content.");
 
             return NULL;
@@ -64,7 +67,7 @@
             || !strcasecmp(mime, "audio/mp4")) {
         return new MPEG4Extractor(source);
     } else if (!strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_MPEG)) {
-        return new MP3Extractor(source);
+        return new MP3Extractor(source, meta);
     } else if (!strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_AMR_NB)
             || !strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_AMR_WB)) {
         return new AMRExtractor(source);
diff --git a/media/libstagefright/OggExtractor.cpp b/media/libstagefright/OggExtractor.cpp
index 9630092..2c1311a 100644
--- a/media/libstagefright/OggExtractor.cpp
+++ b/media/libstagefright/OggExtractor.cpp
@@ -804,7 +804,8 @@
 }
 
 bool SniffOgg(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *) {
     char tmp[4];
     if (source->readAt(0, tmp, 4) < 4 || memcmp(tmp, "OggS", 4)) {
         return false;
diff --git a/media/libstagefright/WAVExtractor.cpp b/media/libstagefright/WAVExtractor.cpp
index 8d820c0..57c1075 100644
--- a/media/libstagefright/WAVExtractor.cpp
+++ b/media/libstagefright/WAVExtractor.cpp
@@ -404,7 +404,8 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 bool SniffWAV(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *) {
     char header[12];
     if (source->readAt(0, header, sizeof(header)) < (ssize_t)sizeof(header)) {
         return false;
diff --git a/media/libstagefright/include/AMRExtractor.h b/media/libstagefright/include/AMRExtractor.h
index db49fe4..1cdf36d 100644
--- a/media/libstagefright/include/AMRExtractor.h
+++ b/media/libstagefright/include/AMRExtractor.h
@@ -22,6 +22,7 @@
 
 namespace android {
 
+struct AMessage;
 class String8;
 
 class AMRExtractor : public MediaExtractor {
@@ -49,7 +50,8 @@
 };
 
 bool SniffAMR(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *);
 
 }  // namespace android
 
diff --git a/media/libstagefright/include/MP3Extractor.h b/media/libstagefright/include/MP3Extractor.h
index 3ce6df3..0e6ccde 100644
--- a/media/libstagefright/include/MP3Extractor.h
+++ b/media/libstagefright/include/MP3Extractor.h
@@ -22,13 +22,14 @@
 
 namespace android {
 
+struct AMessage;
 class DataSource;
 class String8;
 
 class MP3Extractor : public MediaExtractor {
 public:
     // Extractor assumes ownership of "source".
-    MP3Extractor(const sp<DataSource> &source);
+    MP3Extractor(const sp<DataSource> &source, const sp<AMessage> &meta);
 
     virtual size_t countTracks();
     virtual sp<MediaSource> getTrack(size_t index);
@@ -52,7 +53,8 @@
 };
 
 bool SniffMP3(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *meta);
 
 }  // namespace android
 
diff --git a/media/libstagefright/include/MPEG2TSExtractor.h b/media/libstagefright/include/MPEG2TSExtractor.h
index c96973b..1bf4cd1 100644
--- a/media/libstagefright/include/MPEG2TSExtractor.h
+++ b/media/libstagefright/include/MPEG2TSExtractor.h
@@ -9,6 +9,7 @@
 
 namespace android {
 
+struct AMessage;
 struct AnotherPacketSource;
 struct ATSParser;
 struct DataSource;
@@ -47,7 +48,8 @@
 };
 
 bool SniffMPEG2TS(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *);
 
 }  // namespace android
 
diff --git a/media/libstagefright/include/MPEG4Extractor.h b/media/libstagefright/include/MPEG4Extractor.h
index c8663d5..1c9cc7e 100644
--- a/media/libstagefright/include/MPEG4Extractor.h
+++ b/media/libstagefright/include/MPEG4Extractor.h
@@ -23,6 +23,7 @@
 
 namespace android {
 
+struct AMessage;
 class DataSource;
 class SampleTable;
 class String8;
@@ -75,7 +76,8 @@
 };
 
 bool SniffMPEG4(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *);
 
 }  // namespace android
 
diff --git a/media/libstagefright/include/OggExtractor.h b/media/libstagefright/include/OggExtractor.h
index 7066669..1eda025 100644
--- a/media/libstagefright/include/OggExtractor.h
+++ b/media/libstagefright/include/OggExtractor.h
@@ -22,6 +22,7 @@
 
 namespace android {
 
+struct AMessage;
 class DataSource;
 class String8;
 
@@ -53,7 +54,8 @@
 };
 
 bool SniffOgg(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *);
 
 }  // namespace android
 
diff --git a/media/libstagefright/include/WAVExtractor.h b/media/libstagefright/include/WAVExtractor.h
index 3e847b9..df6d3e7 100644
--- a/media/libstagefright/include/WAVExtractor.h
+++ b/media/libstagefright/include/WAVExtractor.h
@@ -22,6 +22,7 @@
 
 namespace android {
 
+struct AMessage;
 class DataSource;
 class String8;
 
@@ -58,7 +59,8 @@
 };
 
 bool SniffWAV(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *);
 
 }  // namespace android
 
diff --git a/media/libstagefright/matroska/MatroskaExtractor.cpp b/media/libstagefright/matroska/MatroskaExtractor.cpp
index 71f6587..7c7d69e 100644
--- a/media/libstagefright/matroska/MatroskaExtractor.cpp
+++ b/media/libstagefright/matroska/MatroskaExtractor.cpp
@@ -579,7 +579,8 @@
 }
 
 bool SniffMatroska(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *) {
     DataSourceReader reader(source);
     mkvparser::EBMLHeader ebmlHeader;
     long long pos;
diff --git a/media/libstagefright/matroska/MatroskaExtractor.h b/media/libstagefright/matroska/MatroskaExtractor.h
index 7471848..fa20b84 100644
--- a/media/libstagefright/matroska/MatroskaExtractor.h
+++ b/media/libstagefright/matroska/MatroskaExtractor.h
@@ -27,6 +27,7 @@
 
 namespace android {
 
+struct AMessage;
 class String8;
 
 struct DataSourceReader;
@@ -69,7 +70,8 @@
 };
 
 bool SniffMatroska(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence);
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *);
 
 }  // namespace android
 
diff --git a/media/libstagefright/mpeg2ts/MPEG2TSExtractor.cpp b/media/libstagefright/mpeg2ts/MPEG2TSExtractor.cpp
index b287c95..56ca375 100644
--- a/media/libstagefright/mpeg2ts/MPEG2TSExtractor.cpp
+++ b/media/libstagefright/mpeg2ts/MPEG2TSExtractor.cpp
@@ -174,7 +174,8 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 bool SniffMPEG2TS(
-        const sp<DataSource> &source, String8 *mimeType, float *confidence) {
+        const sp<DataSource> &source, String8 *mimeType, float *confidence,
+        sp<AMessage> *) {
 #if 0
     char header;
     if (source->readAt(0, &header, 1) != 1 || header != 0x47) {