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• Dreamcast Archival

  24 mai 2011, par Multimedia Mike — Sega Dreamcast

  Console homebrew communities have always had a precarious relationship with console pirates. The same knowledge and skills useful for creating homebrew programs can usually be parlayed into ripping games and cajoling a console into honoring ripped copies. For this reason, the Dreamcast homebrew community tried hard to distance itself from pirates, rippers, and other unsavory characters.

  
  
  

  Funny how times change. While I toed the same line while I was marginally a part of the community back in the day, now I think I’m performing a service for video game archivists and historians by openly publishing the same information. I know of at least one solution already. But I think it’s possible to do much better.

  Pre-existing Art
  Famed Japanese game hacker BERO (FFmpeg contributors should recognize his name from a number of Dreamcast-related multimedia contributions including CRI ADX and SH-4 optimizations) crafted a program called dreamrip based on KOS’s precursor called libdream. This is the program I used to extract 4XM multimedia files from Alone in the Dark : The New Nightmare.

  Fun facts : The Sega Dreamcast used special optical discs called GD-ROMs. The GD stands for ‘GigaDisc’ which implied that they could hold roughly a gigabyte of data. How long do you think it takes to transfer that much data over a serial cable operating at 115,200 bits/second (on the order of 11 Kbytes/sec) ? I seem to recall entire discs requiring on the order of 27-28 hours to archive.

  If only I possessed some expertise in data compression which might expedite this process.

  KallistiOS’ Unwitting Help
  The KallistiOS (KOS) console-oriented RTOS provides all the software infrastructure necessary for archiving (that’s what we’ll call it in this post) Dreamcast games. KOS exposes the optical disc’s filesystem via the /cd mount point on the VFS. From there, KOS provides functions for communicating with a host computer via ethernet (broadband adapter) or serial line (DC coder’s cable). To this end, KOS exposes another mount point on the VFS named /pc which allows direct access to the host PC’s filesystem.

  Thus, it’s pretty straightforward to use KOS to access the files (or raw sectors) of the Dreamcast disc and then send them over the communication line to the host PC. Simple.

  Compressing Before Transfer
  Right away, I wonder about compiling 3 different compression libraries : libz, libbz2, and liblzma. The latter 2 are exceptionally CPU-intensive to compress. Then again, it doesn’t really matter how long the compressor takes to do its job as long as it can average better than 11 Kbytes/sec on a 200MHz Hitachi SH-4 CPU. KOS can be set up in a preemptive threading mode which means it should be possible to read sectors and compress them while keeping the UART operating at full tilt.

  A 4th compression algorithm should be in play here as well : FLAC. Since some of these discs contain red book CD audio tracks that need archival, lossless audio compression should be useful.

  This post serves as a rough overview for possible future experiments. Readers might have further brainstorms.

• Uploading video to Twitter sometimes doesn't work

  22 juillet 2021, par K-s S-k

  I have a very difficult situation. I've already spent 2 days and couldn't find a solution. Project on Laravel. I want to upload videos to Twitter using the Twitter API endpoints. But sometimes I am getting this error :

  


  


  file is currently unsupported

  


  


  I did everything as recommended in the official documentation Video specifications and recommendations. I get an error when I set an audio codec is aac in my video file, despite the fact that it is recommended in the official documentation, but when I set the audio codec to mp3, the video is uploaded, but the sound quality is very poor, and sometimes there is no sound at all. Please forgive me if this is awkward to read, but I want to provide all of my code. Because I don't know how to solve this anymore and I think it might help.

  


  <?php

namespace App\Jobs;

use App\Models\PublishedContent;
use Atymic\Twitter\Facades\Twitter;
use GuzzleHttp\Client as GuzzleClient;
use GuzzleHttp\Exception\GuzzleException;
use Illuminate\Bus\Queueable;
use Illuminate\Support\Facades\Log;
use Illuminate\Support\Facades\File;
use Illuminate\Queue\SerializesModels;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Support\Str;


class PublishToTwitter implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;

    /**
     * @var
     */
    protected $publishingData;

    /**
     * Create a new job instance.
     *
     * @param $publishingData
     */
    public function __construct($publishingData)
    {
        $this->publishingData = $publishingData;
    }

    /**
     * Execute the job.
     *
     * @return void
     */
    public function handle()
    {
        $publishingData = $this->publishingData;

        if (is_array($publishingData)) {
            $publishingResult = $this->publishing(...array_values($publishingData));
            sendNotification($publishingResult['message'], $publishingResult['status'], 'Twitter', $publishingResult['link'], $publishingData['post_name'], $publishingData['user']);
        } else {
            $scheduledData = processingScheduledPost($publishingData);
            $postName = $scheduledData['scheduleData']['post_name'];
            $postContent = $scheduledData['scheduleData']['post_content'];
            $userToken = json_decode($publishingData->user_token,true);
            $requestToken = [
                'token'  => $userToken['oauth_token'],
                'secret' => $userToken['oauth_token_secret'],
            ];
            $publishingResult = $this->publishing($scheduledData['file'], $postName, $postContent, $requestToken);
            $publishingResult['status'] && PublishedContent::add($scheduledData['craft'], $scheduledData['file'], "twitter_share");
            sendResultToUser($publishingData, $scheduledData['user'], $publishingResult['message'], $postName, $publishingResult['link'], $publishingResult['publishing_status'], $scheduledData['social_media']);
            sendNotification($publishingResult['message'], $publishingResult['status'], 'Twitter', $publishingResult['link'], $postName, $scheduledData['user']);
        }
    }

    /**
     * @param $file
     * @param $postName
     * @param $postContent
     * @param $requestToken
     * @return array
     */
    private function publishing($file, $postName, $postContent, $requestToken): array
    {
        $result = [
            'status' => false,
            'link' => null,
            'message' => 'Your content can\'t successfully published on Twitter. This file is not supported for publishing.',
            'publishing_status' => 'error'
        ];

        if ((($file->refe_type !== 'text') || $file->refe_file_path) && !checkIfFileExist($file->refe_file_path)) {
            $result['message'] = 'Missing or invalid file.';
            return $result;
        }

        $filePath = $file->refe_file_path;
        $fileSize = $file->content_length;
        $tempFileName = 'temp-' . $file->refe_file_name;
        $ext = $file->file_type;
        $mediaCategory = 'tweet_' . $file->refe_type;
        $mediaType = $file->refe_type . '/' . $ext;
        $remoteFile = file_get_contents($filePath);
        $tempFolder = public_path('/storage/uploads/temp');

        if (!file_exists($tempFolder)) {
            mkdir($tempFolder, 0777, true);
        }

        $tempFile = public_path('/storage/uploads/temp/' . $tempFileName);
        File::put($tempFile, $remoteFile);
        $convertedFileName = 'converted-' . $file->refe_file_name;
        $convertedFile = public_path('/storage/uploads/temp/' . $convertedFileName);
        $command = 'ffmpeg -y -i '.$tempFile.' -b:v 5000k -b:a 380k -c:a aac -profile:a aac_low -threads 1 '.$convertedFile.'';
        exec($command);
        @File::delete($tempFile);

        try {
            $twitter = Twitter::usingCredentials($requestToken['token'], $requestToken['secret']);
            if ($file->refe_type === 'text') {
                $twitter->postTweet([
                    'status' => urldecode($postContent),
                    'format' => 'json',
                ]);

                $result['link'] = 'https://twitter.com/home';
                $result['status'] = true;
                $result['message'] = 'Your content successfully published on Twitter. You can visit to Twitter and check it.';
                $result['publishing_status'] = 'done';
            } else if ($file->refe_type === 'video' || $file->refe_type === 'image') {
                if ($file->refe_type === 'video') {
                    $duration = getVideoDuration($file->refe_file_path);

                    if ($duration > config('constant.sharing_configs.max_video_duration.twitter')) {
                        throw new \Exception('The duration of the video file must not exceed 140 seconds.');
                    }
                }

                $isFileTypeSupported = checkPublishedFileType('twitter', $file->refe_type, strtolower($ext));
                $isFileSizeSupported = checkPublishedFileSize('twitter', $file->refe_type, $fileSize, strtolower($ext));

                if (!$isFileTypeSupported) {
                    throw new \Exception('Your content can\'t successfully published on Twitter. This file type is not supported for publishing.');
                }

                if (!$isFileSizeSupported) {
                    throw new \Exception('Your content can\'t successfully published on Twitter. The file size is exceeded.');
                }

                if ($file->refe_type === 'video') $fileSize = filesize($convertedFile);

                if (strtolower($ext) === 'gif') {
                    $initMedia = $twitter->uploadMedia([
                        'command' => 'INIT',
                        'total_bytes' => (int)$fileSize
                    ]);
                } else {
                    $initMedia = $twitter->uploadMedia([
                        'command' => 'INIT',
                        'media_type' => $mediaType,
                        'media_category' => $mediaCategory,
                        'total_bytes' => (int)$fileSize
                    ]);
                }

                $mediaId = (int)$initMedia->media_id_string;

                $fp = fopen($convertedFile, 'r');
                $segmentId = 0;

                while (!feof($fp)) {
                    $chunk = fread($fp, 1048576);

                    $twitter->uploadMedia([
                        'media_data' => base64_encode($chunk),
                        'command' => 'APPEND',
                        'segment_index' => $segmentId,
                        'media_id' => $mediaId
                    ]);

                    $segmentId++;
                }

                fclose($fp);

                $twitter->uploadMedia([
                    'command' => 'FINALIZE',
                    'media_id' => $mediaId
                ]);

                if ($file->refe_type === 'video') {
                    $waits = 0;

                    while ($waits <= 4) {
                        // Authorizing header for Twitter API
                        $oauth = [
                            'command' => 'STATUS',
                            'media_id' => $mediaId,
                            'oauth_consumer_key' => config('twitter.consumer_key'),
                            'oauth_nonce' => Str::random(42),
                            'oauth_signature_method' => 'HMAC-SHA1',
                            'oauth_timestamp' => time(),
                            'oauth_token' => $requestToken['token'],
                            'oauth_version' => '1.0'
                        ];

                        // Generate an OAuth 1.0a HMAC-SHA1 signature for an HTTP request
                        $baseInfo = $this->buildBaseString('https://upload.twitter.com/1.1/media/upload.json', 'GET', $oauth);
                        // Getting a signing key
                        $compositeKey = rawurlencode(config('twitter.consumer_secret')) . '&' . rawurlencode($requestToken['secret']);
                        // Calculating the signature
                        $oauthSignature = base64_encode(hash_hmac('sha1', $baseInfo, $compositeKey, true));
                        $oauth['oauth_signature'] = $oauthSignature;
                        $headers['Authorization'] = $this->buildAuthorizationHeader($oauth);

                        try {
                            $guzzle = new GuzzleClient([
                                'headers' => $headers
                            ]);
                            $response = $guzzle->request( 'GET', 'https://upload.twitter.com/1.1/media/upload.json?command=STATUS&media_id=' . $mediaId);
                            $uploadStatus = json_decode($response->getBody()->getContents());
                        } catch (\Exception | GuzzleException $e) {
                            dd($e->getMessage(), $e->getLine(), $e->getFile());
                        }

                        if (isset($uploadStatus->processing_info->state)) {
                            switch ($uploadStatus->processing_info->state) {
                                case 'succeeded':
                                    $waits = 5; // break out of the while loop
                                    break;
                                case 'failed':
                                    File::delete($tempFile);
                                    Log::error('File processing failed: ' . $uploadStatus->processing_info->error->message);
                                    throw new \Exception('File processing failed: ' . $uploadStatus->processing_info->error->message);
                                default:
                                    sleep($uploadStatus->processing_info->check_after_secs);
                                    $waits++;
                            }
                        } else {
                            throw new \Exception('There was an unknown error uploading your file');
                        }
                    }
                }

                $twitter->postTweet(['status' => urldecode($postContent), 'media_ids' => $initMedia->media_id_string]);
                @File::delete($convertedFile);
                $result['link'] = 'https://twitter.com/home';
                $result['status'] = true;
                $result['message'] = 'Your content successfully published on Twitter. You can visit to Twitter and check it.';
                $result['publishing_status'] = 'done';
            }
        } catch (\Exception $e) {
            dd($e->getMessage());
            $result['message'] = $e->getMessage();
            return $result;
        }

        return $result;
    }

    /**
     * @param $baseURI
     * @param $method
     * @param $params
     * @return string
     *
     * Creating the signature base string
     */
    protected function buildBaseString($baseURI, $method, $params): string
    {
        $r = array();
        ksort($params);
        foreach($params as $key=>$value){
            $r[] = "$key=" . rawurlencode($value);
        }
        return $method . "&" . rawurlencode($baseURI) . '&' . rawurlencode(implode('&', $r));
    }

    /**
     * @param $oauth
     * @return string
     *
     * Collecting parameters
     */
    protected function buildAuthorizationHeader($oauth): string
    {
        $r = 'OAuth ';
        $values = array();
        foreach($oauth as $key=>$value)
            $values[] = "$key=\"" . rawurlencode($value) . "\"";
        $r .= implode(', ', $values);
        return $r;
    }
}



  


  I would be very grateful if someone would help me.

  


• Why FFmpeg transcode with strips

  15 septembre 2023, par Андрей Тернити

  I have MJPEG video. I want get VP9 webm video.

  


  ffmpeg -loglevel verbose -i "input.yuvj422p" -pix_fmt yuv420p -c:v libvpx-vp9 -crf 20 -b:v 0 constantQualityExample.webm


  


  And it works ok (right image), log :

  


  [mjpeg @ 0x55b9b4b7ea40] Format mjpeg detected only with low score of 25, misdetection possible!
Input #0, mjpeg, from 'input.yuvj422p':
  Duration: N/A, bitrate: N/A
    Stream #0:0: Video: mjpeg (Baseline), 1 reference frame, yuvj422p(pc, bt470bg/unknown/unknown, center), 1280x720 [SAR 1:1 DAR 16:9], 25 tbr, 1200k tbn, 25 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> vp9 (libvpx-vp9))
Press [q] to stop, [?] for help
[graph 0 input from stream 0:0 @ 0x55b9b4ba4a00] w:1280 h:720 pixfmt:yuvj422p tb:1/1200000 fr:25/1 sar:1/1
[auto_scaler_0 @ 0x55b9b4ba7c00] w:iw h:ih flags:'bicubic' interl:0
[format @ 0x55b9b4ba5800] auto-inserting filter 'auto_scaler_0' between the filter 'Parsed_null_0' and the filter 'format'
[swscaler @ 0x55b9b4ba8b00] deprecated pixel format used, make sure you did set range correctly
[auto_scaler_0 @ 0x55b9b4ba7c00] w:1280 h:720 fmt:yuvj422p sar:1/1 -> w:1280 h:720 fmt:yuv420p sar:1/1 flags:0x4
[libvpx-vp9 @ 0x55b9b4b85840] v1.7.0
[libvpx-vp9 @ 0x55b9b4b85840] --prefix=/usr --enable-pic --enable-shared --disable-install-bins --disable-install-srcs --size-limit=16384x16384 --enable-postproc --enable-multi-res-encoding --enable-temporal-denoising --enable-vp9-temporal-denoising --enable-vp9-postproc --target=x86_64-linux-gcc
Output #0, webm, to 'constantQualityExample.webm':
  Metadata:
    encoder         : Lavf58.45.100
    Stream #0:0: Video: vp9 (libvpx-vp9), 1 reference frame, yuv420p(center), 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 25 fps, 1k tbn, 25 tbc
    Metadata:
      encoder         : Lavc58.91.100 libvpx-vp9
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
No more output streams to write to, finishing.
Automatically inserted bitstream filter 'vp9_superframe'; args=''


  


  But I want the same by libav. I take official example and make a little changes to make code easy (remove audio capabilities, remove multi-video streams capabilities), my code here. But it produce video with strips and drop last frame (left image).

Mediainfo :

My example log :

  


  Input #0, jpeg_pipe, from 'input.yuvj422p':
  Duration: N/A, bitrate: N/A
  Stream #0:0: Video: mjpeg (Baseline), yuvj422p(pc, bt470bg/unknown/unknown), 1280x720 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 25 tbn
[libvpx-vp9 @ 0x5593e186fa80] v1.11.0
Output #0, webm, to 'VideoOut.webm':
  Stream #0:0: Video: vp9, yuv420p(unknown/bt470bg/unknown), 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 25 tbn
[swscaler @ 0x5593e221af00] deprecated pixel format used, make sure you did set range correctly


  


  What I should change in my code to take ok result like ffmpeg ?