java - YouTube 视频下载(Android/Java)-6ren

java - YouTube 视频下载(Android/Java)

转载作者：行者123 更新时间：2023-12-02 01:53:50

注意:原始问题已删除

原始问题是https://stackoverflow.com/questions/15240011/get-the-download-url-for-youtube-video-android-java/15240012#15240012

这里的答案已经过时，不起作用，所以我将发布一个新问题并回答自己

旧代码

new YouTubePageStreamUriGetter().execute("https://www.youtube.com/watch?v=4GuqB1BQVr4");

class Meta {
    public String num;
    public String type;
    public String ext;

    Meta(String num, String ext, String type) {
        this.num = num;
        this.ext = ext;
        this.type = type;
    }
}

class Video {
    public String ext = "";
    public String type = "";
    public String url = "";

    Video(String ext, String type, String url) {
        this.ext = ext;
        this.type = type;
        this.url = url;
    }
}

public ArrayList<Video> getStreamingUrisFromYouTubePage(String ytUrl)
        throws IOException {
    if (ytUrl == null) {
        return null;
    }

    // Remove any query params in query string after the watch?v=<vid> in
    // e.g.
    // http://www.youtube.com/watch?v=0RUPACpf8Vs&feature=youtube_gdata_player
    int andIdx = ytUrl.indexOf('&');
    if (andIdx >= 0) {
        ytUrl = ytUrl.substring(0, andIdx);
    }

    // Get the HTML response
    String userAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:8.0.1)";
    HttpClient client = new DefaultHttpClient();
    client.getParams().setParameter(CoreProtocolPNames.USER_AGENT,
            userAgent);
    HttpGet request = new HttpGet(ytUrl);
    HttpResponse response = client.execute(request);
    String html = "";
    InputStream in = response.getEntity().getContent();
    BufferedReader reader = new BufferedReader(new InputStreamReader(in));
    StringBuilder str = new StringBuilder();
    String line = null;
    while ((line = reader.readLine()) != null) {
        str.append(line.replace("\\u0026", "&"));
    }
    in.close();
    html = str.toString();

    // Parse the HTML response and extract the streaming URIs
    if (html.contains("verify-age-thumb")) {
        CLog.w("YouTube is asking for age verification. We can't handle that sorry.");
        return null;
    }

    if (html.contains("das_captcha")) {
        CLog.w("Captcha found, please try with different IP address.");
        return null;
    }

    Pattern p = Pattern.compile("stream_map\": \"(.*?)?\"");
    // Pattern p = Pattern.compile("/stream_map=(.[^&]*?)\"/");
    Matcher m = p.matcher(html);
    List<String> matches = new ArrayList<String>();
    while (m.find()) {
        matches.add(m.group());
    }

    if (matches.size() != 1) {
        CLog.w("Found zero or too many stream maps.");
        return null;
    }

    String urls[] = matches.get(0).split(",");
    HashMap<String, String> foundArray = new HashMap<String, String>();
    for (String ppUrl : urls) {
        String url = URLDecoder.decode(ppUrl, "UTF-8");

        Pattern p1 = Pattern.compile("itag=([0-9]+?)[&]");
        Matcher m1 = p1.matcher(url);
        String itag = null;
        if (m1.find()) {
            itag = m1.group(1);
        }

        Pattern p2 = Pattern.compile("sig=(.*?)[&]");
        Matcher m2 = p2.matcher(url);
        String sig = null;
        if (m2.find()) {
            sig = m2.group(1);
        }

        Pattern p3 = Pattern.compile("url=(.*?)[&]");
        Matcher m3 = p3.matcher(ppUrl);
        String um = null;
        if (m3.find()) {
            um = m3.group(1);
        }

        if (itag != null && sig != null && um != null) {
            foundArray.put(itag, URLDecoder.decode(um, "UTF-8") + "&"
                    + "signature=" + sig);
        }
    }

    if (foundArray.size() == 0) {
        CLog.w("Couldn't find any URLs and corresponding signatures");
        return null;
    }

    HashMap<String, Meta> typeMap = new HashMap<String, Meta>();
    typeMap.put("13", new Meta("13", "3GP", "Low Quality - 176x144"));
    typeMap.put("17", new Meta("17", "3GP", "Medium Quality - 176x144"));
    typeMap.put("36", new Meta("36", "3GP", "High Quality - 320x240"));
    typeMap.put("5", new Meta("5", "FLV", "Low Quality - 400x226"));
    typeMap.put("6", new Meta("6", "FLV", "Medium Quality - 640x360"));
    typeMap.put("34", new Meta("34", "FLV", "Medium Quality - 640x360"));
    typeMap.put("35", new Meta("35", "FLV", "High Quality - 854x480"));
    typeMap.put("43", new Meta("43", "WEBM", "Low Quality - 640x360"));
    typeMap.put("44", new Meta("44", "WEBM", "Medium Quality - 854x480"));
    typeMap.put("45", new Meta("45", "WEBM", "High Quality - 1280x720"));
    typeMap.put("18", new Meta("18", "MP4", "Medium Quality - 480x360"));
    typeMap.put("22", new Meta("22", "MP4", "High Quality - 1280x720"));
    typeMap.put("37", new Meta("37", "MP4", "High Quality - 1920x1080"));
    typeMap.put("33", new Meta("38", "MP4", "High Quality - 4096x230"));

    ArrayList<Video> videos = new ArrayList<ARViewer.Video>();

    for (String format : typeMap.keySet()) {
        Meta meta = typeMap.get(format);

        if (foundArray.containsKey(format)) {
            Video newVideo = new Video(meta.ext, meta.type,
                    foundArray.get(format));
            videos.add(newVideo);
            CLog.d("YouTube Video streaming details: ext:" + newVideo.ext
                    + ", type:" + newVideo.type + ", url:" + newVideo.url);
        }
    }

    return videos;
}

private class YouTubePageStreamUriGetter extends
        AsyncTask<String, String, String> {
    ProgressDialog progressDialog;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        progressDialog = ProgressDialog.show(ARViewer.this, "",
                "Connecting to YouTube...", true);
    }

    @Override
    protected String doInBackground(String... params) {
        String url = params[0];
        try {
            ArrayList<Video> videos = getStreamingUrisFromYouTubePage(url);
            if (videos != null && !videos.isEmpty()) {
                String retVidUrl = null;
                for (Video video : videos) {
                    if (video.ext.toLowerCase().contains("mp4")
                            && video.type.toLowerCase().contains("medium")) {
                        retVidUrl = video.url;
                        break;
                    }
                }
                if (retVidUrl == null) {
                    for (Video video : videos) {
                        if (video.ext.toLowerCase().contains("3gp")
                                && video.type.toLowerCase().contains(
                                        "medium")) {
                            retVidUrl = video.url;
                            break;

                        }
                    }
                }
                if (retVidUrl == null) {

                    for (Video video : videos) {
                        if (video.ext.toLowerCase().contains("mp4")
                                && video.type.toLowerCase().contains("low")) {
                            retVidUrl = video.url;
                            break;

                        }
                    }
                }
                if (retVidUrl == null) {
                    for (Video video : videos) {
                        if (video.ext.toLowerCase().contains("3gp")
                                && video.type.toLowerCase().contains("low")) {
                            retVidUrl = video.url;
                            break;
                        }
                    }
                }

                return retVidUrl;
            }
        } catch (Exception e) {
            CLog.e("Couldn't get YouTube streaming URL", e);
        }
        CLog.w("Couldn't get stream URI for " + url);
        return null;
    }

    @Override
    protected void onPostExecute(String streamingUrl) {
        super.onPostExecute(streamingUrl);
        progressDialog.dismiss();
        if (streamingUrl != null) {
                         /* Do what ever you want with streamUrl */
        }
    }
}

此代码不起作用

最佳答案

编辑3

您可以使用库:https://github.com/HaarigerHarald/android-youtubeExtractor

例如:

String youtubeLink = "http://youtube.com/watch?v=xxxx";

new YouTubeExtractor(this) {
@Override
public void onExtractionComplete(SparseArray<YtFile> ytFiles, VideoMeta vMeta) {
    if (ytFiles != null) {
        int itag = 22;
    String downloadUrl = ytFiles.get(itag).getUrl();
    }
}
}.extract(youtubeLink, true, true);

他们使用以下方式破译签名:

private boolean decipherSignature(final SparseArray<String> encSignatures) throws IOException {
    // Assume the functions don't change that much
    if (decipherFunctionName == null || decipherFunctions == null) {
        String decipherFunctUrl = "https://s.ytimg.com/yts/jsbin/" + decipherJsFileName;

        BufferedReader reader = null;
        String javascriptFile;
        URL url = new URL(decipherFunctUrl);
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
        urlConnection.setRequestProperty("User-Agent", USER_AGENT);
        try {
            reader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
            StringBuilder sb = new StringBuilder("");
            String line;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
                sb.append(" ");
            }
            javascriptFile = sb.toString();
        } finally {
            if (reader != null)
                reader.close();
            urlConnection.disconnect();
        }

        if (LOGGING)
            Log.d(LOG_TAG, "Decipher FunctURL: " + decipherFunctUrl);
        Matcher mat = patSignatureDecFunction.matcher(javascriptFile);
        if (mat.find()) {
            decipherFunctionName = mat.group(1);
            if (LOGGING)
                Log.d(LOG_TAG, "Decipher Functname: " + decipherFunctionName);

            Pattern patMainVariable = Pattern.compile("(var |\\s|,|;)" + decipherFunctionName.replace("$", "\\$") +
                    "(=function\\((.{1,3})\\)\\{)");

            String mainDecipherFunct;

            mat = patMainVariable.matcher(javascriptFile);
            if (mat.find()) {
                mainDecipherFunct = "var " + decipherFunctionName + mat.group(2);
            } else {
                Pattern patMainFunction = Pattern.compile("function " + decipherFunctionName.replace("$", "\\$") +
                        "(\\((.{1,3})\\)\\{)");
                mat = patMainFunction.matcher(javascriptFile);
                if (!mat.find())
                    return false;
                mainDecipherFunct = "function " + decipherFunctionName + mat.group(2);
            }

            int startIndex = mat.end();

            for (int braces = 1, i = startIndex; i < javascriptFile.length(); i++) {
                if (braces == 0 && startIndex + 5 < i) {
                    mainDecipherFunct += javascriptFile.substring(startIndex, i) + ";";
                    break;
                }
                if (javascriptFile.charAt(i) == '{')
                    braces++;
                else if (javascriptFile.charAt(i) == '}')
                    braces--;
            }
            decipherFunctions = mainDecipherFunct;
            // Search the main function for extra functions and variables
            // needed for deciphering
            // Search for variables
            mat = patVariableFunction.matcher(mainDecipherFunct);
            while (mat.find()) {
                String variableDef = "var " + mat.group(2) + "={";
                if (decipherFunctions.contains(variableDef)) {
                    continue;
                }
                startIndex = javascriptFile.indexOf(variableDef) + variableDef.length();
                for (int braces = 1, i = startIndex; i < javascriptFile.length(); i++) {
                    if (braces == 0) {
                        decipherFunctions += variableDef + javascriptFile.substring(startIndex, i) + ";";
                        break;
                    }
                    if (javascriptFile.charAt(i) == '{')
                        braces++;
                    else if (javascriptFile.charAt(i) == '}')
                        braces--;
                }
            }
            // Search for functions
            mat = patFunction.matcher(mainDecipherFunct);
            while (mat.find()) {
                String functionDef = "function " + mat.group(2) + "(";
                if (decipherFunctions.contains(functionDef)) {
                    continue;
                }
                startIndex = javascriptFile.indexOf(functionDef) + functionDef.length();
                for (int braces = 0, i = startIndex; i < javascriptFile.length(); i++) {
                    if (braces == 0 && startIndex + 5 < i) {
                        decipherFunctions += functionDef + javascriptFile.substring(startIndex, i) + ";";
                        break;
                    }
                    if (javascriptFile.charAt(i) == '{')
                        braces++;
                    else if (javascriptFile.charAt(i) == '}')
                        braces--;
                }
            }

            if (LOGGING)
                Log.d(LOG_TAG, "Decipher Function: " + decipherFunctions);
            decipherViaWebView(encSignatures);
            if (CACHING) {
                writeDeciperFunctToChache();
            }
        } else {
            return false;
        }
    } else {
        decipherViaWebView(encSignatures);
    }
    return true;
}

现在使用这个库高质量视频丢失音频，所以我使用 MediaMuxer用于合并音频和视频以进行最终输出

编辑 1

https://stackoverflow.com/a/15240012/9909365

为什么之前的答案不起作用

 Pattern p2 = Pattern.compile("sig=(.*?)[&]");
        Matcher m2 = p2.matcher(url);
        String sig = null;
        if (m2.find()) {
            sig = m2.group(1);
        }

As of November 2016, this is a little rough around the edges, but displays the basic principle. The url_encoded_fmt_stream_map today does not have a space after the colon (better make this optional) and "sig" has been changed to "signature"

and while i am debuging the code i found the new keyword its signature&s in many video's URL

这里编辑了答案

private static final HashMap<String, Meta> typeMap = new HashMap<String, Meta>();

initTypeMap();先打电话

class Meta {
    public String num;
    public String type;
    public String ext;

    Meta(String num, String ext, String type) {
        this.num = num;
        this.ext = ext;
        this.type = type;
    }
}

class Video {
    public String ext = "";
    public String type = "";
    public String url = "";

    Video(String ext, String type, String url) {
        this.ext = ext;
        this.type = type;
        this.url = url;
    }
}

public ArrayList<Video> getStreamingUrisFromYouTubePage(String ytUrl)
        throws IOException {
    if (ytUrl == null) {
        return null;
    }

    // Remove any query params in query string after the watch?v=<vid> in
    // e.g.
    // http://www.youtube.com/watch?v=0RUPACpf8Vs&feature=youtube_gdata_player
    int andIdx = ytUrl.indexOf('&');
    if (andIdx >= 0) {
        ytUrl = ytUrl.substring(0, andIdx);
    }

    // Get the HTML response
    /* String userAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:8.0.1)";*/
   /* HttpClient client = new DefaultHttpClient();
    client.getParams().setParameter(CoreProtocolPNames.USER_AGENT,
            userAgent);
    HttpGet request = new HttpGet(ytUrl);
    HttpResponse response = client.execute(request);*/
    String html = "";
    HttpsURLConnection c = (HttpsURLConnection) new URL(ytUrl).openConnection();
    c.setRequestMethod("GET");
    c.setDoOutput(true);
    c.connect();
    InputStream in = c.getInputStream();
    BufferedReader reader = new BufferedReader(new InputStreamReader(in));
    StringBuilder str = new StringBuilder();
    String line = null;
    while ((line = reader.readLine()) != null) {
        str.append(line.replace("\\u0026", "&"));
    }
    in.close();
    html = str.toString();

    // Parse the HTML response and extract the streaming URIs
    if (html.contains("verify-age-thumb")) {
        Log.e("Downloader", "YouTube is asking for age verification. We can't handle that sorry.");
        return null;
    }

    if (html.contains("das_captcha")) {
        Log.e("Downloader", "Captcha found, please try with different IP address.");
        return null;
    }

    Pattern p = Pattern.compile("stream_map\":\"(.*?)?\"");
    // Pattern p = Pattern.compile("/stream_map=(.[^&]*?)\"/");
    Matcher m = p.matcher(html);
    List<String> matches = new ArrayList<String>();
    while (m.find()) {
        matches.add(m.group());
    }

    if (matches.size() != 1) {
        Log.e("Downloader", "Found zero or too many stream maps.");
        return null;
    }

    String urls[] = matches.get(0).split(",");
    HashMap<String, String> foundArray = new HashMap<String, String>();
    for (String ppUrl : urls) {
        String url = URLDecoder.decode(ppUrl, "UTF-8");
        Log.e("URL","URL : "+url);

        Pattern p1 = Pattern.compile("itag=([0-9]+?)[&]");
        Matcher m1 = p1.matcher(url);
        String itag = null;
        if (m1.find()) {
            itag = m1.group(1);
        }

        Pattern p2 = Pattern.compile("signature=(.*?)[&]");
        Matcher m2 = p2.matcher(url);
        String sig = null;
        if (m2.find()) {
            sig = m2.group(1);
        } else {
            Pattern p23 = Pattern.compile("signature&s=(.*?)[&]");
            Matcher m23 = p23.matcher(url);
            if (m23.find()) {
                sig = m23.group(1);
            }
        }

        Pattern p3 = Pattern.compile("url=(.*?)[&]");
        Matcher m3 = p3.matcher(ppUrl);
        String um = null;
        if (m3.find()) {
            um = m3.group(1);
        }

        if (itag != null && sig != null && um != null) {
            Log.e("foundArray","Adding Value");
            foundArray.put(itag, URLDecoder.decode(um, "UTF-8") + "&"
                    + "signature=" + sig);
        }
    }
    Log.e("foundArray","Size : "+foundArray.size());
    if (foundArray.size() == 0) {
        Log.e("Downloader", "Couldn't find any URLs and corresponding signatures");
        return null;
    }


    ArrayList<Video> videos = new ArrayList<Video>();

    for (String format : typeMap.keySet()) {
        Meta meta = typeMap.get(format);

        if (foundArray.containsKey(format)) {
            Video newVideo = new Video(meta.ext, meta.type,
                    foundArray.get(format));
            videos.add(newVideo);
            Log.d("Downloader", "YouTube Video streaming details: ext:" + newVideo.ext
                    + ", type:" + newVideo.type + ", url:" + newVideo.url);
        }
    }

    return videos;
}

private class YouTubePageStreamUriGetter extends AsyncTask<String, String, ArrayList<Video>> {
    ProgressDialog progressDialog;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        progressDialog = ProgressDialog.show(webViewActivity.this, "",
                "Connecting to YouTube...", true);
    }

    @Override
    protected ArrayList<Video> doInBackground(String... params) {
        ArrayList<Video> fVideos = new ArrayList<>();
        String url = params[0];
        try {
            ArrayList<Video> videos = getStreamingUrisFromYouTubePage(url);
            /*                Log.e("Downloader","Size of Video : "+videos.size());*/
            if (videos != null && !videos.isEmpty()) {
                for (Video video : videos)
                {
                    Log.e("Downloader", "ext : " + video.ext);
                    if (video.ext.toLowerCase().contains("mp4") || video.ext.toLowerCase().contains("3gp") || video.ext.toLowerCase().contains("flv") || video.ext.toLowerCase().contains("webm")) {
                        ext = video.ext.toLowerCase();
                        fVideos.add(new Video(video.ext,video.type,video.url));
                    }
                }


                return fVideos;
            }
        } catch (Exception e) {
            e.printStackTrace();
            Log.e("Downloader", "Couldn't get YouTube streaming URL", e);
        }
        Log.e("Downloader", "Couldn't get stream URI for " + url);
        return null;
    }

    @Override
    protected void onPostExecute(ArrayList<Video> streamingUrl) {
        super.onPostExecute(streamingUrl);
        progressDialog.dismiss();
        if (streamingUrl != null) {
            if (!streamingUrl.isEmpty()) {
                //Log.e("Steaming Url", "Value : " + streamingUrl);

                for (int i = 0; i < streamingUrl.size(); i++) {
                    Video fX = streamingUrl.get(i);
                    Log.e("Founded Video", "URL : " + fX.url);
                    Log.e("Founded Video", "TYPE : " + fX.type);
                    Log.e("Founded Video", "EXT : " + fX.ext);
                }
                //new ProgressBack().execute(new String[]{streamingUrl, filename + "." + ext});
            }
        }
    }
}
public void initTypeMap()
{
    typeMap.put("13", new Meta("13", "3GP", "Low Quality - 176x144"));
    typeMap.put("17", new Meta("17", "3GP", "Medium Quality - 176x144"));
    typeMap.put("36", new Meta("36", "3GP", "High Quality - 320x240"));
    typeMap.put("5", new Meta("5", "FLV", "Low Quality - 400x226"));
    typeMap.put("6", new Meta("6", "FLV", "Medium Quality - 640x360"));
    typeMap.put("34", new Meta("34", "FLV", "Medium Quality - 640x360"));
    typeMap.put("35", new Meta("35", "FLV", "High Quality - 854x480"));
    typeMap.put("43", new Meta("43", "WEBM", "Low Quality - 640x360"));
    typeMap.put("44", new Meta("44", "WEBM", "Medium Quality - 854x480"));
    typeMap.put("45", new Meta("45", "WEBM", "High Quality - 1280x720"));
    typeMap.put("18", new Meta("18", "MP4", "Medium Quality - 480x360"));
    typeMap.put("22", new Meta("22", "MP4", "High Quality - 1280x720"));
    typeMap.put("37", new Meta("37", "MP4", "High Quality - 1920x1080"));
    typeMap.put("33", new Meta("38", "MP4", "High Quality - 4096x230"));
}

编辑2:

Some time This Code Not worked proper

同源策略

https://en.wikipedia.org/wiki/Same-origin_policy

https://en.wikipedia.org/wiki/Cross-origin_resource_sharing

problem of Same-origin policy. Essentially, you cannot download this file from www.youtube.com because they are different domains. A workaround of this problem is [CORS][1].

引用号:https://superuser.com/questions/773719/how-do-all-of-these-save-video-from-youtube-services-work/773998#773998

url_encoded_fmt_stream_map // traditional: contains video and audio stream
adaptive_fmts              // DASH: contains video or audio stream

其中每一个都是一个逗号分隔的数组，我称之为“流对象”。每个“流对象”将包含这样的值

url  // direct HTTP link to a video
itag // code specifying the quality
s    // signature, security measure to counter downloading

每个 URL 都将被编码，因此您需要对其进行解码。现在是棘手的部分。

YouTube 的视频至少有 3 个安全级别

unsecured // as expected, you can download these with just the unencoded URL
s         // see below
RTMPE     // uses "rtmpe://" protocol, no known method for these

RTMPE 视频通常用于官方完整长度的电影，并受到 SWF 验证类型 2 的保护。这自 2011 年以来就已存在，尚未进行逆向工程。

“s”类型的视频实际上是最难下载的。您通常会在 VEVO 视频等上看到这些。它们以签名开头，例如

AA5D05FA7771AD4868BA4C977C3DEAAC620DE020E.0F421820F42978A1F8EAFCDAC4EF507DB5然后用这样的函数对签名进行加扰

function mo(a) {
  a = a.split("");
  a = lo.rw(a, 1);
  a = lo.rw(a, 32);
  a = lo.IC(a, 1);
  a = lo.wS(a, 77);
  a = lo.IC(a, 3);
  a = lo.wS(a, 77);
  a = lo.IC(a, 3);
  a = lo.wS(a, 44);
  return a.join("")
}

此函数是动态的，通常每天都会发生变化。为了使其变得更加困难，该函数托管在诸如

之类的 URL 上

http://s.ytimg.com/yts/jsbin/html5player-en_US-vflycBCEX.js

这就引入了同源策略的问题。本质上，您无法从 www.youtube.com 下载此文件，因为它们是不同的域。此问题的解决方法是 CORS。通过 CORS，s.ytimg.com 可以添加此 header

Access-Control-Allow-Origin: http://www.youtube.com

并且它将允许从 www.youtube.com 下载 JavaScript。他们当然不这样做。此解决方法的解决方法是使用 CORS 代理。这是一个代理，它使用以下 header 响应所有请求

Access-Control-Allow-Origin: *

现在您已经代理了 JS 文件，并使用该函数来扰乱签名，您可以在查询字符串中使用它来下载视频。

关于java - YouTube 视频下载(Android/Java)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/52588551/

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