Simplify Subrip support

This commit is contained in:
Oliver Woodman 2015-06-10 17:48:01 +01:00
parent 71252784e9
commit fbbf3f27fd
4 changed files with 60 additions and 149 deletions

View File

@ -25,24 +25,10 @@ import com.google.android.exoplayer.text.Cue;
public final long startTime;
public final long endTime;
public SubripCue(CharSequence text) {
this(Cue.UNSET_VALUE, Cue.UNSET_VALUE, Cue.UNSET_VALUE,text);
}
public SubripCue(long startTime, long endTime, int position, CharSequence text) {
super(text, Cue.UNSET_VALUE, position, null, Cue.UNSET_VALUE);
public SubripCue(long startTime, long endTime, CharSequence text) {
super(text);
this.startTime = startTime;
this.endTime = endTime;
}
/**
* Returns whether or not this cue should be placed in the default position and rolled-up with
* the other "normal" cues.
*
* @return True if this cue should be placed in the default position; false otherwise.
*/
public boolean isNormalCue() {
return (line == UNSET_VALUE && position == UNSET_VALUE);
}
}

View File

@ -15,14 +15,15 @@
*/
package com.google.android.exoplayer.text.subrip;
import android.text.Html;
import com.google.android.exoplayer.C;
import com.google.android.exoplayer.ParserException;
import com.google.android.exoplayer.text.Cue;
import com.google.android.exoplayer.text.SubtitleParser;
import com.google.android.exoplayer.util.MimeTypes;
import android.text.Html;
import android.text.Spanned;
import android.text.TextUtils;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
@ -32,93 +33,66 @@ import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* A simple SRT parser.
* A simple SubRip parser.
* <p/>
*
* @see <a href="https://en.wikipedia.org/wiki/SubRip">Wikipedia on SRT</a>
* @see <a href="https://en.wikipedia.org/wiki/SubRip">Wikipedia on SubRip</a>
*/
public final class SubripParser implements SubtitleParser {
private static final String TAG = "SubRipParser";
private static final String SUBRIP_POSITION_STRING = "^(\\d)$";
private static final Pattern SUBRIP_POSITION = Pattern.compile(SUBRIP_POSITION_STRING);
private static final String SUBRIP_CUE_IDENTIFIER_STRING = "^(.*)\\s-->\\s(.*)$";
private static final Pattern SUBRIP_CUE_IDENTIFIER =
Pattern.compile(SUBRIP_CUE_IDENTIFIER_STRING);
private static final String SUBRIP_TIMESTAMP_STRING = "(\\d+:)?[0-5]\\d:[0-5]\\d:[0-5]\\d,\\d{3}";
// private static final Pattern SUBRIP_TIMESTAMP = Pattern.compile(SUBRIP_TIMESTAMP_STRING);
private static final Pattern SUBRIP_TIMING_LINE = Pattern.compile("(.*)\\s+-->\\s+(.*)");
private static final Pattern SUBRIP_TIMESTAMP =
Pattern.compile("(?:(\\d+):)?(\\d+):(\\d+),(\\d+)");
private final StringBuilder textBuilder;
private final boolean strictParsing;
public SubripParser() {
this(true);
}
public SubripParser(boolean strictParsing) {
this.strictParsing = strictParsing;
textBuilder = new StringBuilder();
}
@Override
public SubripSubtitle parse(InputStream inputStream, String inputEncoding, long startTimeUs)
throws IOException {
ArrayList<SubripCue> subtitles = new ArrayList<>();
ArrayList<SubripCue> cues = new ArrayList<>();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, C.UTF8_NAME));
String currentLine;
// file should not be empty
if (inputStream.available() == 0) {
throw new ParserException("File is empty?");
}
BufferedReader subripData = new BufferedReader(new InputStreamReader(inputStream, C.UTF8_NAME));
String line;
// process the cues and text
while ((line = subripData.readLine()) != null) {
long startTime = Cue.UNSET_VALUE;
long endTime = Cue.UNSET_VALUE;
CharSequence text = null;
int position = Cue.UNSET_VALUE;
Matcher matcher = SUBRIP_POSITION.matcher(line);
if (matcher.matches()) {
position = Integer.parseInt(matcher.group());
while ((currentLine = reader.readLine()) != null) {
// Parse the numeric counter as a sanity check.
try {
Integer.parseInt(currentLine);
} catch (NumberFormatException e) {
throw new ParserException("Expected numeric counter: " + currentLine);
}
line = subripData.readLine();
// parse cue time
matcher = SUBRIP_CUE_IDENTIFIER.matcher(line);
if (!matcher.find()) {
throw new ParserException("Expected cue start time: " + line);
// Read and parse the timing line.
long cueStartTimeUs;
long cueEndTimeUs;
currentLine = reader.readLine();
Matcher matcher = SUBRIP_TIMING_LINE.matcher(currentLine);
if (matcher.find()) {
cueStartTimeUs = parseTimestampUs(matcher.group(1)) + startTimeUs;
cueEndTimeUs = parseTimestampUs(matcher.group(2)) + startTimeUs;
} else {
startTime = parseTimestampUs(matcher.group(1)) + startTimeUs;
endTime = parseTimestampUs(matcher.group(2)) + startTimeUs;
throw new ParserException("Expected timing line: " + currentLine);
}
// parse text
// Read and parse the text.
textBuilder.setLength(0);
while (((line = subripData.readLine()) != null) && (!line.isEmpty())) {
while (!TextUtils.isEmpty(currentLine = reader.readLine())) {
if (textBuilder.length() > 0) {
textBuilder.append("<br>");
}
textBuilder.append(line.trim());
textBuilder.append(currentLine.trim());
}
text = Html.fromHtml(textBuilder.toString());
SubripCue cue = new SubripCue(startTime, endTime, position, text);
subtitles.add(cue);
Spanned text = Html.fromHtml(textBuilder.toString());
SubripCue cue = new SubripCue(cueStartTimeUs, cueEndTimeUs, text);
cues.add(cue);
}
subripData.close();
reader.close();
inputStream.close();
SubripSubtitle subtitle = new SubripSubtitle(subtitles, startTimeUs);
SubripSubtitle subtitle = new SubripSubtitle(cues, startTimeUs);
return subtitle;
}
@ -127,23 +101,16 @@ public final class SubripParser implements SubtitleParser {
return MimeTypes.APPLICATION_SUBRIP.equals(mimeType);
}
private void handleNoncompliantLine(String line) throws ParserException {
if (strictParsing) {
throw new ParserException("Unexpected line: " + line);
}
}
private static long parseTimestampUs(String s) throws NumberFormatException {
if (!s.matches(SUBRIP_TIMESTAMP_STRING)) {
Matcher matcher = SUBRIP_TIMESTAMP.matcher(s);
if (!matcher.matches()) {
throw new NumberFormatException("has invalid format");
}
String[] parts = s.split(",", 2);
long value = 0;
for (String group : parts[0].split(":")) {
value = value * 60 + Long.parseLong(group);
}
return (value * 1000 + Long.parseLong(parts[1])) * 1000;
long timestampMs = Long.parseLong(matcher.group(1)) * 60 * 60 * 1000;
timestampMs += Long.parseLong(matcher.group(2)) * 60 * 1000;
timestampMs += Long.parseLong(matcher.group(3)) * 1000;
timestampMs += Long.parseLong(matcher.group(4));
return timestampMs * 1000;
}
}

View File

@ -15,15 +15,11 @@
*/
package com.google.android.exoplayer.text.subrip;
import android.text.SpannableStringBuilder;
import com.google.android.exoplayer.text.Cue;
import com.google.android.exoplayer.text.Subtitle;
import com.google.android.exoplayer.util.Assertions;
import com.google.android.exoplayer.util.Util;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
@ -36,7 +32,6 @@ import java.util.List;
private final int numCues;
private final long startTimeUs;
private final long[] cueTimesUs;
private final long[] sortedCueTimesUs;
/**
* @param cues A list of the cues in this subtitle.
@ -44,19 +39,16 @@ import java.util.List;
*/
public SubripSubtitle(List<SubripCue> cues, long startTimeUs) {
this.cues = cues;
numCues = cues.size();
this.startTimeUs = startTimeUs;
this.cueTimesUs = new long[2 * numCues];
numCues = cues.size();
cueTimesUs = new long[2 * numCues];
for (int cueIndex = 0; cueIndex < numCues; cueIndex++) {
SubripCue cue = cues.get(cueIndex);
int arrayIndex = cueIndex * 2;
cueTimesUs[arrayIndex] = cue.startTime;
cueTimesUs[arrayIndex + 1] = cue.endTime;
}
this.sortedCueTimesUs = Arrays.copyOf(cueTimesUs, cueTimesUs.length);
Arrays.sort(sortedCueTimesUs);
}
@Override
@ -67,20 +59,20 @@ import java.util.List;
@Override
public int getNextEventTimeIndex(long timeUs) {
Assertions.checkArgument(timeUs >= 0);
int index = Util.binarySearchCeil(sortedCueTimesUs, timeUs, false, false);
return index < sortedCueTimesUs.length ? index : -1;
int index = Util.binarySearchCeil(cueTimesUs, timeUs, false, false);
return index < cueTimesUs.length ? index : -1;
}
@Override
public int getEventTimeCount() {
return sortedCueTimesUs.length;
return cueTimesUs.length;
}
@Override
public long getEventTime(int index) {
Assertions.checkArgument(index >= 0);
Assertions.checkArgument(index < sortedCueTimesUs.length);
return sortedCueTimesUs[index];
Assertions.checkArgument(index < cueTimesUs.length);
return cueTimesUs[index];
}
@Override
@ -88,50 +80,17 @@ import java.util.List;
if (getEventTimeCount() == 0) {
return -1;
}
return sortedCueTimesUs[sortedCueTimesUs.length - 1];
return cueTimesUs[cueTimesUs.length - 1];
}
@Override
public List<Cue> getCues(long timeUs) {
ArrayList<Cue> list = null;
SubripCue firstNormalCue = null;
SpannableStringBuilder normalCueTextBuilder = null;
for (int i = 0; i < numCues; i++) {
if ((cueTimesUs[i * 2] <= timeUs) && (timeUs < cueTimesUs[i * 2 + 1])) {
if (list == null) {
list = new ArrayList<>();
}
SubripCue cue = cues.get(i);
if (cue.isNormalCue()) {
// we want to merge all of the normal cues into a single cue to ensure they are drawn
// correctly (i.e. don't overlap) and to emulate roll-up, but only if there are multiple
// normal cues, otherwise we can just append the single normal cue
if (firstNormalCue == null) {
firstNormalCue = cue;
} else if (normalCueTextBuilder == null) {
normalCueTextBuilder = new SpannableStringBuilder();
normalCueTextBuilder.append(firstNormalCue.text).append("\n").append(cue.text);
} else {
normalCueTextBuilder.append("\n").append(cue.text);
}
} else {
list.add(cue);
}
}
}
if (normalCueTextBuilder != null) {
// there were multiple normal cues, so create a new cue with all of the text
list.add(new SubripCue(normalCueTextBuilder));
} else if (firstNormalCue != null) {
// there was only a single normal cue, so just add it to the list
list.add(firstNormalCue);
}
if (list != null) {
return list;
} else {
int index = Util.binarySearchFloor(cueTimesUs, timeUs, true, false);
if (index == -1 || index % 2 == 1) {
// timeUs is earlier than the start of the first cue, or corresponds to a gap between cues.
return Collections.<Cue>emptyList();
} else {
return Collections.singletonList((Cue) cues.get(index / 2));
}
}

View File

@ -44,18 +44,17 @@ public class WebvttSubtitle implements Subtitle {
*/
public WebvttSubtitle(List<WebvttCue> cues, long startTimeUs) {
this.cues = cues;
numCues = cues.size();
this.startTimeUs = startTimeUs;
this.cueTimesUs = new long[2 * numCues];
numCues = cues.size();
cueTimesUs = new long[2 * numCues];
for (int cueIndex = 0; cueIndex < numCues; cueIndex++) {
WebvttCue cue = cues.get(cueIndex);
int arrayIndex = cueIndex * 2;
cueTimesUs[arrayIndex] = cue.startTime;
cueTimesUs[arrayIndex + 1] = cue.endTime;
}
this.sortedCueTimesUs = Arrays.copyOf(cueTimesUs, cueTimesUs.length);
sortedCueTimesUs = Arrays.copyOf(cueTimesUs, cueTimesUs.length);
Arrays.sort(sortedCueTimesUs);
}