Downloading flv from youtube using curlpp on top of curl - video not playing

问题

I"m using curlpp on to of curl lib in order to download videos from youtube.

I have managed to download the flv but unable to open it using all sorts of video players.

I used another youtube video downloader and download the exactly same video with the exactly same quality, I've noticed the requests are the same and also the file size is almost identical - here I think is the problem, For example: MyVideo.flv - 4.55MB WorkingVideo.flv - 4.53MB

Here is the code:

// Callback Function size_t FileCallback(FILE f, char ptr, size_t size, size_t nmemb) { return fwrite(ptr, size, nmemb, f); }

void GetVideo(std::wstring videoUrl) {

    FILE * file = fopen("C:\\locatin\\b.flv", "w");

if (file)
{
    curlpp::Cleanup cleaner;
    curlpp::Easy request;

    // Set the writer callback to enable cURL to write result in a memory area
    curlpp::types::WriteFunctionFunctor functor(utilspp::BindFirst(utilspp::make_functor(&FileCallback), file));
    curlpp::options::WriteFunction *getFileOpt = new curlpp::options::WriteFunction(functor);
    request.setOpt(getFileOpt);

    // Setting the URL to retrive.
    request.setOpt(new curlpp::options::Url(videoUrl));
    request.setOpt(new curlpp::options::Verbose(true));
    request.setOpt(new Timeout(2000));

    std::list<std::string> headers;
    headers.push_back("Connection: keep-alive");
    headers.push_back("Keep-Alive: 115");
    headers.push_back("Accept-Encoding: gzip,deflate");
    headers.push_back("Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7");
    headers.push_back("User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.10) Gecko/20100914 Firefox/3.6.10");
    headers.push_back("Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
    headers.push_back("Accept-Language: en-us,en;q=0.5");

    request.setOpt<HttpHeader>(headers);
    request.perform();

    fclose(file);
}

}

Any ideas anyone??

Thanks.

回答1:

Since I"m developing on windows platform I've decided that for downloading the file I'll use URLDownloadToFile Info: http://msdn.microsoft.com/en-us/library/ms775123%28VS.85%29.aspx

This one works like a charm, Still not sure why curl saves the file a little bit different than IE or FF or the above win32 api function.

回答2:

Youtube can provide videos encoded on several formats like h263 (flashvideo), h264, etc. Which format are you downloading? (this site also has good information of youtube audio/video formats)

Use a tool to verify the file's header and make sure that what you downloaded is ok! If you are on *nix you can execute file on the command line: file filename.flv

Another possibility is that you may not have the codec needed to play the video. This could explain why no video player on your system is able to play the video you downloaded.

来源：https://stackoverflow.com/questions/3850934/downloading-flv-from-youtube-using-curlpp-on-top-of-curl-video-not-playing

标签

curl

youtube

curlpp