The video player doesn't display remote subtitles with VTT format.

[a-radwan]

Why the video player doesn't supports subtitles with VTT format.

Installed with

• [x] Cocoapods

Issue Description

The video player doesn't display remote subtitles with VTT format. I tried it for remote link url

        subtitleURL = URL(string:"https://subtitlesLink")
    
   let asset = BMPlayerResource(url: URL(string: viewModel.externalURL)!,
                                     name: viewModel.name,
                                    cover: nil,
                                    subtitle:strURL)

I also tried a locally vtt file

        let strURL = Bundle.main.url(forResource: "subtitles_englishc", withExtension: "vtt")!
        let subtitle = BMSubtitles(url: strURL)
        let asset = BMPlayerResource(name: viewModel.name,
                                     definitions: [BMPlayerResourceDefinition(url: URL(string: viewModel.externalURL)!, definition: "")],
                                     cover: nil,
                                     subtitles: subtitle)
                self.player.setVideo(resource: asset)

```the same issue, no subtitles displayed

### What

[BrikerMan]

I only implemented str subtitle parser, so it can't support vtt file.

[a-radwan]

To whom who wants to use this library with VTT format subtitle, you can do the following,

• read the remote VTT subtitle file.
• Convert it to SRT format.
• Save it and load it from the documents directory.

Here you can find my formatter. Stackoverflow question link

+ (NSString *)srtSubtitleFromVTT:(NSString *)content {
    
    NSArray *lines = [self split:content];
    NSString *output = @"";
    NSInteger i = 0;
    NSError *error;
    NSString *newLine;
    
    for (NSString *line in lines) {
        newLine = line;
        NSCharacterSet* notDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];
        
        if([[line stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"\n\r "]]  rangeOfCharacterFromSet:notDigits].location == NSNotFound) {
            continue;
        }
        
        NSString *pattern1 = @"(\\d{2}):(\\d{2}):(\\d{2})\\.(\\d{3})"; // '01:52:52.554'
        NSString *pattern2 = @"(\\d{2}):(\\d{2})\\.(\\d{3})"; // '00:08.301'
        
        NSRegularExpression* regex = [NSRegularExpression regularExpressionWithPattern: pattern1 options:0 error:&error];
        NSArray* matches = [regex matchesInString:line options:0 range: NSMakeRange(0, line.length)];
        
        NSString *pattern ;
        NSString *template;
        
        if (matches.count) {
            pattern = pattern1;
            template = @"$1:$2:$3,$4";
        } else {
            regex = [NSRegularExpression regularExpressionWithPattern: pattern2 options:0 error:&error];
            matches = [regex matchesInString:line options:0 range: NSMakeRange(0, line.length)];
            if (matches.count) {
                pattern = pattern2;
                template = @"00:$1:$2,$3";
            }
        }
        
        if (matches.count && !error) {
            i++;
            output = [output stringByAppendingString:@"\r\n\r\n"];
            output = [output stringByAppendingString:[@(i) stringValue]];
            output = [output stringByAppendingString:@"\r\n"];
            
            newLine = [line stringByReplacingWithPattern:pattern withTemplate:template error:&error];
        }
        
        if([newLine containsString:@"WEBVTT"]) {
            continue;
        }
        output = [output stringByAppendingString:newLine];
        output = [output stringByAppendingString:@"\r\n"];
    }
    
    return output;
}
+ (NSArray *)split:(NSString *)content {
    
    NSArray *lines = [content componentsSeparatedByString: @"\n"];
    if (lines.count == 1) {
        lines  = [content componentsSeparatedByString: @"\r\n"];
        if (lines.count == 1) {
            lines  = [content componentsSeparatedByString: @"\n"];
        }
    }
    return lines;
}

[allenlinli]

Hi @a-radwan, the function stringByReplacingWithPattern is deprecated I think.

[a-radwan]

@allenlinli ,its a utility I have implemented

- (NSString *)stringByReplacingWithPattern:(NSString *)pattern withTemplate:(NSString *)template error:(NSError **)error {
    NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:pattern
                                                                           options:NSRegularExpressionCaseInsensitive
                                                                             error:error];
    return [regex stringByReplacingMatchesInString:self
                                           options:0
                                             range:NSMakeRange(0, self.length)
                                      withTemplate:template];
}