TIKA-4802: Expose the MP4 video bitrate (video:bitrate)

tika-core/src/main/java/org/apache/tika/metadata/Video.java

@@ -0,0 +1,33 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.tika.metadata;
+
+/**
+ * Video metadata properties that have no suitable XMPDM equivalent.
+ * See TIKA-4802.
+ *
+ * @since Apache Tika 4.0.0
+ */
+public interface Video {
+
+    /**
+     * Average bitrate in bits per second, from the video track's BitRateBox
+     * ('btrt'). A per-stream value: in a file with several video tracks it
+     * reflects the last one.
+     */
+    Property BITRATE = Property.internalInteger("video:bitrate");
+}

tika-metadata-schema/src/main/resources/org/apache/tika/metadata/metadata-key-fields.json

@@ -487,6 +487,7 @@
   {"class":"org.apache.tika.metadata.TikaPagedText","field":"PAGE_NUMBER","key":"tk:page:number"},
   {"class":"org.apache.tika.metadata.TikaPagedText","field":"PAGE_NUMBERS","key":"tk:page:numbers"},
   {"class":"org.apache.tika.metadata.TikaPagedText","field":"PAGE_ROTATION","key":"tk:page:rotation"},
+  {"class":"org.apache.tika.metadata.Video","field":"BITRATE","key":"video:bitrate"},
   {"class":"org.apache.tika.metadata.WARC","field":"WARC_PAYLOAD_CONTENT_TYPE","key":"warc:payload-content-type"},
   {"class":"org.apache.tika.metadata.WARC","field":"WARC_RECORD_CONTENT_TYPE","key":"warc:record-content-type"},
   {"class":"org.apache.tika.metadata.WARC","field":"WARC_RECORD_ID","key":"warc:WARC-Record-ID"},

tika-metadata-schema/src/main/resources/org/apache/tika/metadata/metadata-keys.json

@@ -505,6 +505,7 @@
   {"key":"tk:version-count","namespace":"tk","valueType":"INTEGER","cardinality":"SIMPLE"},
   {"key":"tk:version-number","namespace":"tk","valueType":"INTEGER","cardinality":"SIMPLE"},
   {"key":"tk:warn:truncated-metadata","namespace":"tk","valueType":"BOOLEAN","cardinality":"SIMPLE"},
+  {"key":"video:bitrate","namespace":"video","valueType":"INTEGER","cardinality":"SIMPLE"},
   {"key":"w:Comments","namespace":"w","valueType":"TEXT","cardinality":"BAG"},
   {"key":"warc:WARC-Record-ID","namespace":"warc","valueType":"TEXT","cardinality":"SIMPLE"},
   {"key":"warc:payload-content-type","namespace":"warc","valueType":"TEXT","cardinality":"SIMPLE"},

tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-audiovideo-module/src/main/java/org/apache/tika/parser/mp4/TikaMp4BoxHandler.java

@@ -123,6 +123,12 @@ public Mp4Handler<?> processBox(@NotNull String box, @Nullable byte[] payload,
             //sound track: our handler additionally reads DRM markers and the
             //esds average bitrate from the sample description
             return new TikaMp4SoundHandler(metadata, context, tikaMetadata);
+        } else if (box.equals("hdlr") && payload != null && payload.length >= 12
+                && payload[8] == 'v' && payload[9] == 'i'
+                && payload[10] == 'd' && payload[11] == 'e') {
+            //video track: our handler additionally reads the btrt average
+            //bitrate from the sample description
+            return new TikaMp4VideoHandler(metadata, context, tikaMetadata);
         }
 
         return super.processBox(box, payload, size, context);

tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-audiovideo-module/src/main/java/org/apache/tika/parser/mp4/TikaMp4VideoHandler.java

@@ -0,0 +1,111 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.tika.parser.mp4;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import com.drew.imaging.mp4.Mp4Handler;
+import com.drew.metadata.Metadata;
+import com.drew.metadata.mp4.Mp4Context;
+import com.drew.metadata.mp4.media.Mp4VideoHandler;
+
+import org.apache.tika.io.EndianUtils;
+import org.apache.tika.metadata.Video;
+
+/**
+ * Extends the video track handling with what the base handler does not read
+ * from the sample description: the average bitrate from the 'btrt' BitRateBox.
+ * See TIKA-4802.
+ */
+class TikaMp4VideoHandler extends Mp4VideoHandler {
+
+    /**
+     * Fixed size of a VisualSampleEntry (ISO/IEC 14496-12) before its child
+     * boxes: the 8 byte box header, 8 bytes of SampleEntry (6 reserved, 2 data
+     * reference index) and 70 bytes of visual fields ending with the 32 byte
+     * compressor name, the depth and a pre-defined field.
+     */
+    private static final int VISUAL_ENTRY_SIZE = 86;
+
+    private final org.apache.tika.metadata.Metadata tikaMetadata;
+
+    TikaMp4VideoHandler(Metadata metadata, Mp4Context context,
+                        org.apache.tika.metadata.Metadata tikaMetadata) {
+        super(metadata, context);
+        this.tikaMetadata = tikaMetadata;
+    }
+
+    @Override
+    public Mp4Handler<?> processBox(String type, byte[] payload, long boxSize,
+                                    Mp4Context context) throws IOException {
+        if ("stsd".equals(type) && payload != null) {
+            extractFromSampleDescriptions(payload);
+        }
+        return super.processBox(type, payload, boxSize, context);
+    }
+
+    /**
+     * Walks the sample description entries: 4 bytes version and flags, a
+     * 4 byte entry count, then one sample entry per count, each starting with
+     * its own size and format fourcc.
+     */
+    private void extractFromSampleDescriptions(byte[] b) {
+        if (b.length < 8) {
+            return;
+        }
+        long entryCount = EndianUtils.getUIntBE(b, 4);
+        int pos = 8;
+        for (long i = 0; i < entryCount && pos + 8 <= b.length; i++) {
+            long size = EndianUtils.getUIntBE(b, pos);
+            if (size < 16 || size > b.length - pos) {
+                break;
+            }
+            int end = pos + (int) size;
+            int bitRate = findBtrtAverageBitRate(b, pos + VISUAL_ENTRY_SIZE, end);
+            if (bitRate > 0) {
+                tikaMetadata.set(Video.BITRATE, bitRate);
+            }
+            pos = end;
+        }
+    }
+
+    /**
+     * Scans the child boxes of a sample entry for a 'btrt' BitRateBox and
+     * returns its average bitrate, or 0 if there is none. The box body is the
+     * decoding buffer size, the maximum bitrate and the average bitrate.
+     */
+    private static int findBtrtAverageBitRate(byte[] b, int pos, int end) {
+        while (pos >= 0 && pos + 8 <= end) {
+            long size = EndianUtils.getUIntBE(b, pos);
+            if (size < 8 || size > end - pos) {
+                return 0;
+            }
+            if ("btrt".equals(fourCc(b, pos + 4)) && pos + 20 <= end) {
+                long averageBitRate = EndianUtils.getUIntBE(b, pos + 16);
+                return averageBitRate > 0 && averageBitRate <= Integer.MAX_VALUE
+                        ? (int) averageBitRate : 0;
+            }
+            pos += (int) size;
+        }
+        return 0;
+    }
+
+    private static String fourCc(byte[] b, int pos) {
+        return new String(b, pos, 4, StandardCharsets.ISO_8859_1);
+    }
+}

tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-audiovideo-module/src/test/java/org/apache/tika/parser/mp4/MP4ParserTest.java

@@ -46,6 +46,7 @@
 import org.apache.tika.metadata.Metadata;
 import org.apache.tika.metadata.QuickTime;
 import org.apache.tika.metadata.TikaCoreProperties;
+import org.apache.tika.metadata.Video;
 import org.apache.tika.metadata.XMP;
 import org.apache.tika.metadata.XMPDM;
 import org.apache.tika.parser.ParseContext;
@@ -142,8 +143,16 @@ public void testMP4ParsingAudio() throws Exception {
         //TODO: why don't we check the output here?
     }
 
-    // TODO Test a MP4 Video file
     // TODO Test an old QuickTime Video File
+    @Test
+    public void testVideoBitrate() throws Exception {
+        // a 10 fps H.264 clip generated with ffmpeg (color source, 16x16, 1s);
+        // libx264 writes the average bitrate into the btrt BitRateBox
+        XMLResult r = getXML("testMP4Video.mp4");
+        assertEquals("video/mp4", r.metadata.get(Metadata.CONTENT_TYPE));
+        assertEquals("6536", r.metadata.get(Video.BITRATE));
+    }
+
     @Test
     @Timeout(30000)
     public void testInfiniteLoop() throws Exception {