Files
android_development/samples/AtscTvInput/src/com/example/android/atsctvinput/SectionParser.java
Dongwon Kang 0113785a39 Add sample ATSC TvInputService app.
Change-Id: I67204020bf1eb0c833d507cb0c9e4914e5985b3c
2014-04-22 13:45:04 +09:00

406 lines
15 KiB
Java

/*
* Copyright (C) 2014 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.
*/
package com.example.android.atsctvinput;
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/**
* PSIP section parser which conforms to ATSC A/65.
*/
public class SectionParser {
private static final String TAG = "SectionParser";
private static final boolean DEBUG = false;
private static final byte TABLE_ID_MGT = (byte) 0xc7;
private static final byte TABLE_ID_TVCT = (byte) 0xc8;
private static final byte TABLE_ID_CVCT = (byte) 0xc9;
private static final byte TABLE_ID_EIT = (byte) 0xcb;
private static final byte COMPRESSION_TYPE_NO_COMPRESSION = (byte) 0x00;
private static final byte MODE_SELECTED_UNICODE_RANGE_1 = (byte) 0x00; // 0x0000 - 0x00ff
private static final byte MODE_UTF16 = (byte) 0x3f;
private static final int MAX_SHORT_NAME_BYTES = 14;
/*
* The following CRC table is from the generated code by the following command.
* $ python pycrc.py --model crc-32-mpeg --algorithm table-driven --generate c
* To see the details of pycrc, please visit http://www.tty1.net/pycrc/index_en.html
*/
private static final int [] CRC_TABLE = {
0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,
0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005,
0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011,
0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81,
0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d,
0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae,
0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02,
0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692,
0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686,
0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a,
0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47,
0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7,
0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b,
0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f,
0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24,
0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654,
0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0,
0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c,
0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
};
public interface OutputListener {
void onMGTParsed(List<MGTItem> items);
void onVCTParsed(List<VCTItem> items);
void onEITParsed(int sourceId, List<EITItem> items);
}
public static class MGTItem {
public static final int TABLE_TYPE_EIT_0 = 0x0100;
private int mTableType;
private int mTableTypePid;
public MGTItem(int tableType, int tableTypePid) {
mTableType = tableType;
mTableTypePid = tableTypePid;
}
public int getTableType() {
return mTableType;
}
public int getTableTypePid() {
return mTableTypePid;
}
}
public static class VCTItem {
private String mShortName;
private int mProgramNumber;
private int mMajorChannelNumber;
private int mMinorChannelNumber;
private int mSourceId;
public VCTItem(String shortName, int programNumber, int majorChannelNumber,
int minorChannelNumber, int sourceId) {
mShortName = shortName;
mProgramNumber = programNumber;
mMajorChannelNumber = majorChannelNumber;
mMinorChannelNumber = minorChannelNumber;
mSourceId = sourceId;
}
public String getShortName() {
return mShortName;
}
public int getProgramNumber() {
return mProgramNumber;
}
public int getMajorChannelNumber() {
return mMajorChannelNumber;
}
public int getMinorChannelNumber() {
return mMinorChannelNumber;
}
public int getSourceId() {
return mSourceId;
}
}
public static class EITItem {
private String mTitleText;
private long mStartTime;
private int mLengthInSecond;
public EITItem(String titleText, long startTime, int lengthInSecond) {
mTitleText = titleText;
mStartTime = startTime;
mLengthInSecond = lengthInSecond;
}
public String getTitleText() {
return mTitleText;
}
public long getStartTime() {
return mStartTime;
}
public int getLengthInSecond() {
return mLengthInSecond;
}
}
private OutputListener mListener;
public SectionParser(OutputListener listener) {
mListener = listener;
}
public void parseSection(byte[] data) {
if (!checkSanity(data)) {
Log.d(TAG, "Bad CRC!");
return;
}
switch (data[0]) {
case TABLE_ID_MGT:
parseMGT(data);
break;
case TABLE_ID_TVCT:
case TABLE_ID_CVCT:
parseVCT(data);
break;
case TABLE_ID_EIT:
parseEIT(data);
break;
default:
break;
}
}
private void parseMGT(byte[] data) {
// For details of the structure for MGT, please see ATSC A/65 Table 6.2.
if (DEBUG) {
Log.d(TAG, "MGT is discovered.");
}
int tablesDefined = ((data[9] & 0xff) << 8) | (data[10] & 0xff);
int pos = 11;
List<MGTItem> results = new ArrayList<MGTItem>();
for (int i = 0; i < tablesDefined; ++i) {
int tableType = ((data[pos] & 0xff) << 8) | (data[pos + 1] & 0xff);
int tableTypePid = ((data[pos + 2] & 0x1f) << 8) | (data[pos + 3] & 0xff);
int descriptorsLength = ((data[pos + 9] & 0x0f) << 8) | (data[pos + 10] & 0xff);
pos += 11 + descriptorsLength;
if (pos >= data.length) {
Log.d(TAG, "Broken MGT.");
return;
}
results.add(new MGTItem(tableType, tableTypePid));
}
if ((data[pos] & 0xf0) != 0xf0) {
Log.d(TAG, "Broken MGT.");
return;
}
if (mListener != null) {
mListener.onMGTParsed(results);
}
}
private void parseVCT(byte[] data) {
// For details of the structure for VCT, please see ATSC A/65 Table 6.4 and 6.8.
if (DEBUG) {
Log.d(TAG, "VCT is discovered.");
}
int sectionNumber = (data[6] & 0xff);
int lastSectionNumber = (data[7] & 0xff);
int numChannelsInSection = (data[9] & 0xff);
int pos = 10;
List<VCTItem> results = new ArrayList<VCTItem>();
for (int i = 0; i < numChannelsInSection; ++i) {
String shortName = "";
int shortNameSize = getShortNameSize(data, pos);
try {
shortName = new String(
Arrays.copyOfRange(data, pos, pos + shortNameSize), "UTF-16");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
if ((data[pos + 14] & 0xf0) != 0xf0) {
Log.d(TAG, "Broken VCT.");
return;
}
int majorNumber = ((data[pos + 14] & 0x0f) << 6) | ((data[pos + 15] & 0xff) >> 2);
int minorNumber = ((data[pos + 15] & 0x03) << 8) | (data[pos + 16] & 0xff);
if ((majorNumber & 0x3f0) == 0x3f0) {
// If the six MSBs are 111111, these indicate that there is only one-part channel
// number. To see details, please refer A/65 Section 6.3.2.
majorNumber = ((majorNumber & 0xf) << 10) + minorNumber;
minorNumber = 0;
}
int programNumber = ((data[pos + 24] & 0xff) << 8) | (data[pos + 25] & 0xff);
int sourceId = ((data[pos + 28] & 0xff) << 8) | (data[pos + 29] & 0xff);
int descriptorsLength = ((data[pos + 30] & 0x03) << 8) | (data[pos + 31] & 0xff);
pos += 32 + descriptorsLength;
if (pos >= data.length) {
Log.d(TAG, "Broken VCT.");
return;
}
results.add(new VCTItem(shortName, programNumber, majorNumber, minorNumber, sourceId));
}
if ((data[pos] & 0xfc) != 0xfc) {
Log.d(TAG, "Broken VCT.");
return;
}
if (mListener != null) {
mListener.onVCTParsed(results);
}
}
private void parseEIT(byte[] data) {
// For details of the structure for EIT, please see ATSC A/65 Table 6.11.
if (DEBUG) {
Log.d(TAG, "EIT is discovered.");
}
int sourceId = ((data[3] & 0xff) << 8) | (data[4] & 0xff);
int sectionNumber = (data[6] & 0xff);
int lastSectionNumber = (data[7] & 0xff);
int numEventsInSection = (data[9] & 0xff);
int pos = 10;
List<EITItem> results = new ArrayList<EITItem>();
for (int i = 0; i < numEventsInSection; ++i) {
if ((data[pos] & 0xc0) != 0xc0) {
Log.d(TAG, "Broken EIT.");
return;
}
long startTime = ((data[pos + 2] & (long) 0xff) << 24) | ((data[pos + 3] & 0xff) << 16)
| ((data[pos + 4] & 0xff) << 8) | (data[pos + 5] & 0xff);
int lengthInSecond = ((data[pos + 6] & 0x0f) << 16)
| ((data[pos + 7] & 0xff) << 8) | (data[pos + 8] & 0xff);
int titleLength = (data[pos + 9] & 0xff);
String titleText = "";
if (titleLength > 0) {
titleText = extractText(data, pos + 10);
}
if ((data[pos + 10 + titleLength] & 0xf0) != 0xf0) {
Log.d(TAG, "Broken EIT.");
return;
}
int descriptorsLength = ((data[pos + 10 + titleLength] & 0x0f) << 8)
| (data[pos + 10 + titleLength + 1] & 0xff);
pos += 10 + titleLength + 2 + descriptorsLength;
if (pos >= data.length) {
Log.d(TAG, "Broken EIT.");
return;
}
results.add(new EITItem(titleText, startTime, lengthInSecond));
}
if (mListener != null) {
mListener.onEITParsed(sourceId, results);
}
}
private int getShortNameSize(byte[] data, int offset) {
for (int i = 0; i < MAX_SHORT_NAME_BYTES; i += 2) {
if(data[offset + i] == 0 && data[offset + i + 1] == 0) {
return i;
}
}
return MAX_SHORT_NAME_BYTES;
}
private String extractText(byte[] data, int startOffset) {
int pos = startOffset;
int numStrings = data[pos] & 0xff;
pos++;
for (int i = 0; i < numStrings; ++i) {
int numSegments = data[pos + 3] & 0xff;
pos += 4;
for (int j = 0; j < numSegments; ++j) {
int compressionType = data[pos] & 0xff;
int mode = data[pos + 1] & 0xff;
int numBytes = data[pos + 2] & 0xff;
if (compressionType == COMPRESSION_TYPE_NO_COMPRESSION) {
try {
if (mode == MODE_UTF16) {
return new String(Arrays.copyOfRange(
data, pos + 3, pos + 3 + numBytes), "UTF-16");
} else if (mode == MODE_SELECTED_UNICODE_RANGE_1){
return new String(Arrays.copyOfRange(
data, pos + 3, pos + 3 + numBytes), "UTF-8");
}
} catch (UnsupportedEncodingException e) {
System.out.println("Unsupported text format.");
}
}
pos += 3 + numBytes;
}
}
return null;
}
private boolean checkSanity(byte[] data) {
boolean hasCRC = (data[1] & 0x80) != 0; // section_syntax_indicator
if (hasCRC) {
int crc = 0xffffffff;
for(byte b : data) {
int index = ((crc >> 24) ^ (b & 0xff)) & 0xff;
crc = CRC_TABLE[index] ^ (crc << 8);
}
if(crc != 0){
return false;
}
}
return true;
}
}