1 files changed, 118 insertions, 0 deletions
diff --git a/media/libstagefright/timedtext/TimedTextInBandSource.cpp b/media/libstagefright/timedtext/TimedTextInBandSource.cpp
new file mode 100644
index 0000000..f2c4d54
--- /dev/null
+++ b/media/libstagefright/timedtext/TimedTextInBandSource.cpp
@@ -0,0 +1,118 @@
+ /*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "TimedTextInBandSource"
+#include <utils/Log.h>
+
+#include <binder/Parcel.h>
+#include <media/stagefright/MediaBuffer.h>
+#include <media/stagefright/MediaDebug.h>  // CHECK_XX macro
+#include <media/stagefright/MediaDefs.h>  // for MEDIA_MIMETYPE_xxx
+#include <media/stagefright/MediaErrors.h>
+#include <media/stagefright/MediaSource.h>
+#include <media/stagefright/MetaData.h>
+
+#include "TimedTextInBandSource.h"
+#include "TextDescriptions.h"
+
+namespace android {
+
+TimedTextInBandSource::TimedTextInBandSource(const sp<MediaSource>& mediaSource)
+    : mSource(mediaSource) {
+}
+
+TimedTextInBandSource::~TimedTextInBandSource() {
+}
+
+status_t TimedTextInBandSource::read(
+        int64_t *timeUs, Parcel *parcel, const MediaSource::ReadOptions *options) {
+    MediaBuffer *textBuffer = NULL;
+    status_t err = mSource->read(&textBuffer, options);
+    if (err != OK) {
+        return err;
+    }
+    CHECK(textBuffer != NULL);
+    textBuffer->meta_data()->findInt64(kKeyTime, timeUs);
+    // TODO: this is legacy code. when 'timeUs' can be <= 0?
+    if (*timeUs > 0) {
+        extractAndAppendLocalDescriptions(*timeUs, textBuffer, parcel);
+    }
+    textBuffer->release();
+    return OK;
+}
+
+// Each text sample consists of a string of text, optionally with sample
+// modifier description. The modifier description could specify a new
+// text style for the string of text. These descriptions are present only
+// if they are needed. This method is used to extract the modifier
+// description and append it at the end of the text.
+status_t TimedTextInBandSource::extractAndAppendLocalDescriptions(
+        int64_t timeUs, const MediaBuffer *textBuffer, Parcel *parcel) {
+    const void *data;
+    size_t size = 0;
+    int32_t flag = TextDescriptions::LOCAL_DESCRIPTIONS;
+
+    const char *mime;
+    CHECK(mSource->getFormat()->findCString(kKeyMIMEType, &mime));
+
+    if (strcasecmp(mime, MEDIA_MIMETYPE_TEXT_3GPP) == 0) {
+        data = textBuffer->data();
+        size = textBuffer->size();
+
+        if (size > 0) {
+            parcel->freeData();
+            flag |= TextDescriptions::IN_BAND_TEXT_3GPP;
+            return TextDescriptions::getParcelOfDescriptions(
+                    (const uint8_t *)data, size, flag, timeUs / 1000, parcel);
+        }
+        return OK;
+    }
+    return ERROR_UNSUPPORTED;
+}
+
+// To extract and send the global text descriptions for all the text samples
+// in the text track or text file.
+// TODO: send error message to application via notifyListener()...?
+status_t TimedTextInBandSource::extractGlobalDescriptions(Parcel *parcel) {
+    const void *data;
+    size_t size = 0;
+    int32_t flag = TextDescriptions::GLOBAL_DESCRIPTIONS;
+
+    const char *mime;
+    CHECK(mSource->getFormat()->findCString(kKeyMIMEType, &mime));
+
+    // support 3GPP only for now
+    if (strcasecmp(mime, MEDIA_MIMETYPE_TEXT_3GPP) == 0) {
+        uint32_t type;
+        // get the 'tx3g' box content. This box contains the text descriptions
+        // used to render the text track
+        if (!mSource->getFormat()->findData(
+                kKeyTextFormatData, &type, &data, &size)) {
+            return ERROR_MALFORMED;
+        }
+
+        if (size > 0) {
+            flag |= TextDescriptions::IN_BAND_TEXT_3GPP;
+            return TextDescriptions::getParcelOfDescriptions(
+                    (const uint8_t *)data, size, flag, 0, parcel);
+        }
+        return OK;
+    }
+    return ERROR_UNSUPPORTED;
+}
+
+}  // namespace android