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  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Creating farms of unique websites

    13 avril 2011, par

    MediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
    This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...)

  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

Sur d’autres sites (3403)

  • Alias Artifacts

    26 avril 2013, par Multimedia Mike — General

    Throughout my own life, I have often observed that my own sense of nostalgia has a window that stretches about 10-15 years past from the current moment. Earlier this year, I discovered the show “Alias” and watched through the entire series thanks to Amazon Prime Instant Video (to be fair, I sort of skimmed the fifth and final season which I found to be horribly dull, or maybe franchise fatigue had set in). The show originally aired from 2001-2006 so I found that it fit well within the aforementioned nostalgia window.


    Alias (TV Series) logo

    But what was it, exactly, about the show that triggered nostalgia ? The computers, of course ! The show revolved around spies and espionage and cutting-edge technology necessarily played a role. The production designer for the series must have decided that Unix/Linux == awesome hacking and so many screenshots featured Linux.

    Since this is still nominally a multimedia blog, I’ll start of the screenshot recon with an old multimedia player. Here is a vintage Mac OS desktop running an ancient web browser (probably Netscape) that’s playing a full-window video (probably QuickTime embedded directly into the browser).


    Old Mac OS with old browser

    Click for larger image


    Let’s jump right into the Linux side of things. This screenshot makes me particularly sentimental since this is exactly what a stock Linux/KDE desktop looked like circa 2001-2003 and is more or less what I would have worked with on my home computer at the time :


    Alias: Linux/KDE desktop

    Click for larger image


    Studying that screenshot, we see that the user logs in as root, even to the desktop environment. Poor security practice ; I would expect better from a bunch of spooks.

    Echelon
    Look at the terminal output in the above screenshot– it’s building a program named Echelon, an omniscient spy tool inspired by a real-world surveillance network of the same name. In the show, Echelon is used to supply plot-convenient intelligence. At one point, some antagonists get their hands on the Echelon source code and seek to compile it. When they do, they will have access to the vast surveillance network. If you know anything about how computers work, don’t think about that too hard.

    Anyway, it’s interesting to note that Echelon is a properly autotool’d program– when the bad guys finally got Echelon, installation was just a ‘make install’ command away. The compilation was very user-friendly, though, as it would pop up a nice dialog box showing build progress :


    Alias: Compiling Echelon

    Click for larger image


    Examining the build lines in both that screenshot and the following lines, we can see that Echelon cares about files such as common/db_err.c and bt_curadj.c :


    Alias: Echelon used Berkeley DB

    Click for larger image


    A little googling reveals that these files both belong to the Berkeley DB library. That works ; I can imagine a program like this leveraging various database packages.

    Computer Languages
    The Echelon source code stuff comes from episode 2.11 : “A Higher Echelon”. While one faction had gotten a hold of the actual Echelon source code, a rival faction had abducted the show’s resident uber-nerd and, learning that they didn’t actually receive the Echelon code, force the nerd to re-write Echelon from scratch. Which he then proceeds to do…


    Alias: Rewriting Echelon

    Click for larger image


    The code he’s examining there appears to be C code that has something to do with joystick programming (JS_X_0, JS_Y_1, etc.). An eagle-eyed IMDb user contributed the trivia that he is looking at the file /usr/include/Linux/joystick.h.

    Getting back to the plot, how could the bad buys possibly expect him to re-write a hugely complex piece of software from scratch ? You might think this is the height of absurdity for a computer-oriented story. You’ll be pleased to know that the writers agreed with that assessment since, when the program was actually executed, it claimed to be Echelon, but that broke into a game of Pong (or some simple game). Suddenly, it makes perfect sense why the guy was looking at the joystick header file.

    This is the first bit of computer-oriented fun that I captured when I was watching the series :


    Alias: Java on the mainframe

    Click for larger image


    This printout purports to be a “mainframe log summary”. After some plot-advancing text about a security issue, it proceeds to dump out some Java source code.

    SSH
    Secure Shell (SSH) frequently showed up. Here’s a screenshot in which a verbose ‘ssh -v’ connection has just been closed, while a telnet command has apparently just been launched (evidenced by “Escape character is ‘^]’.”) :


    Alias: SSH/telnet

    Click for larger image


    This is followed by some good old Hollywood Hacking in which a free-form database command is entered through any available command line interface :


    Alias: Intuitive command line interface

    Click for larger image


    I don’t remember the episode details, but I’m pretty sure the output made perfect sense to the character typing the command. Here’s another screenshot where the SSH client pops up an extra-large GUI dialog element to notify the user that it’s currently negotiating with the host :


    Alias: SSH negotiation dialog

    Click for larger image


    Now that I look at that screenshot a little more closely, it appears to be a Win95/98 program. I wonder if there was an SSH client that actually popped up that gaudy dialog.

    There’s a lot of gibberish in this screenshot and I wish I had written down some details about what it represented according to the episode’s plot :


    Alias: Public key

    Click for larger image


    It almost sounds like they were trying to break into a network computer. Analyzing MD5 structure… public key synthesized. To me, the funniest feature is the 7-digit public key. I’m a bit rusty on the math of the RSA cryptosystem, but intuitively, it seems that the public and private keys need to be of roughly equal lengths. I.e., the private key in this scenario would also be 7 digits long.

    Gadgets
    Various devices and gadgets were seen at various junctures in the show. Here’s a tablet computer from back when tablet computers seemed like fantastical (albeit stylus-requiring) devices– the Fujitsu Stylistic 2300 :


    Alias: Fujitsu Stylistic 2300 tablet

    Click for larger image


    Here’s a videophone from an episode that aired in 2005. The specific model is the Packet8 DV326 (MSRP of US$500). As you can see from the screenshot, it can do 384 kbps both down and up.


    Alias: Packet8 DV326

    Click for larger image


    I really regret not writing down the episode details surrounding this gadget. I just know that it was critical that the good guys get it and keep from falling into the hands of the bad guys.


    Alias: Gadget using Samsung and Lexar chips

    Click for larger image


    As you can see, the (presumably) deadly device contains a Samsung chip and a Lexar chip. I have to wonder what device the production crew salvaged this from (probably just an old cell phone).

    Other Programs

    The GIMP photo editor makes an appearance while scrubbing security camera footage, and serves as the magical Enhance Button (at least they slung around the term “gamma”) :


    Alias: GIMP editor

    Click for larger image


    I have no idea what MacOS-based audio editing program this is. Any ideas ?


    Alias: Apple MacOS-based audio editor

    Click for larger image


    FTP shows up in episode 2.12, “The Getaway”. It’s described as a “secure channel” for communication, which is quite humorous to anyone versed in internet technology.


    Alias: FTP secure channel

    Click for larger image


  • Getting Error during executin native android code

    3 avril 2013, par dilipkaklotar

    Error on my console

    bash : cannot set terminal process group (-1) : Inappropriate ioctl for device
    bash : no job control in this shell
    Your group is currently "mkpasswd". This indicates that your
    gid is not in /etc/group and your uid is not in /etc/passwd.

    The /etc/passwd (and possibly /etc/group) files should be rebuilt.
    See the man pages for mkpasswd and mkgroup then, for example, run

    mkpasswd -l [-d] > /etc/passwd
    mkgroup -l [-d] > /etc/group

    Note that the -d switch is necessary for domain users.
    - ]0 ; -
    - [32mDILIP@DILIP-PC -[33m -[0m
    $

    public class VideoBrowser extends ListActivity implements ListView.OnScrollListener {

    /*this part communicates with native code through jni (java native interface)*/
    //load the native library
    static {
       System.loadLibrary("ffmpeg");
       System.loadLibrary("ffmpeg-test-jni");
    }
    //declare the jni functions
    private static native void naInit(String _videoFileName);
    private static native int[] naGetVideoResolution();
    private static native String naGetVideoCodecName();
    private static native String naGetVideoFormatName();
    private static native void naClose();

    private void showVideoInfo(final File _file) {
       String videoFilename = _file.getAbsolutePath();
       naInit(videoFilename);
       int[] prVideoRes = naGetVideoResolution();
       String prVideoCodecName = naGetVideoCodecName();
       String prVideoFormatName = naGetVideoFormatName();
       naClose();
       String displayText = "Video: " + videoFilename + "\n";
       displayText += "Video Resolution: " + prVideoRes[0] + "x" + prVideoRes[1] + "\n";
       displayText += "Video Codec: " + prVideoCodecName + "\n";
       displayText += "Video Format: " + prVideoFormatName + "\n";
       text_titlebar_text.setText(displayText);
    }


    /*the rest of the file deals with UI and other stuff*/
    private Context mContext;
    public static VideoBrowser self;

    /**
    * activity life cycle: this part of the source code deals with activity life cycle
    */
    @Override
    public void onCreate(Bundle icicle) {
       super.onCreate(icicle);
       mContext = this.getApplicationContext();
       self = this;
       initUI();
    }

    @Override
    protected void onDestroy() {
       super.onDestroy();
       unbindDisplayEntries();
    }

    public void unbindDisplayEntries() {
       if (displayEntries!=null) {
           int l_count = displayEntries.size();
           for (int i = 0; i < l_count; ++i) {
               IconifiedTextSelected l_its = displayEntries.get(i);
               if (l_its != null) {
                   Drawable l_dr = l_its.getIcon();
                   if (l_dr != null) {
                       l_dr.setCallback(null);
                       l_dr = null;
                   }
               }
           }
       }
       if (l_displayEntries!=null) {
           int l_count = l_displayEntries.size();
           for (int i = 0; i < l_count; ++i) {
               IconifiedTextSelected l_its = l_displayEntries.get(i);
               if (l_its != null) {
                   Drawable l_dr = l_its.getIcon();
                   if (l_dr != null) {
                       l_dr.setCallback(null);
                       l_dr = null;
                   }
               }
           }
       }
    }

    /**
    * Data: this part of the code deals with data processing
    */
    public List<iconifiedtextselected> displayEntries = new ArrayList<iconifiedtextselected>();
    public static List<iconifiedtextselected> l_displayEntries = new ArrayList<iconifiedtextselected>();;

    /**load images
    * this part of code deals with loading of images
    */
    private File currentDirectory;
    public int media_browser_load_option = 2;
    private static int last_media_browser_load_option = 2;
    private static int number_of_icons = 0;
    private static final String upOneLevel = "..";

    LoadVideoTask loadTask;
    private void loadVideosFromDirectory(String _dir) {
       try {
           loadTask = new LoadVideoTask();
           loadTask.execute(_dir);
       } catch (Exception e) {
           Toast.makeText(this, "Load media fail!", Toast.LENGTH_SHORT).show();
       }
    }

    private void getVideosFromDirectoryNonRecurAddParent(File _dir) {
       //add the upper one level data
       if (_dir.getParent()!=null) {
           this.displayEntries.add(new IconifiedTextSelected(
                   upOneLevel,
                   getResources().getDrawable(R.drawable.folderback),
                   false, false, 0));
       }
    }

    private void getVideosFromDirectoryNonRecur(File _dir) {
       Drawable folderIcon = this.getResources().getDrawable(R.drawable.normalfolder);
       //add the
       if (!_dir.isDirectory()) {
           return;
       }
       File[] files = _dir.listFiles();
       if (files == null) {
           return;
       }
       Drawable videoIcon = null;
       int l_iconType = 0;
       for (File currentFile : files) {
           if (currentFile.isDirectory()) {
               //if it&#39;s a directory
               this.displayEntries.add(new IconifiedTextSelected(
                       currentFile.getPath(),
                       folderIcon, false, false, 0));
           } else {
               String l_filename = currentFile.getName();
               if (checkEndsWithInStringArray(l_filename,
                           getResources().getStringArray(R.array.fileEndingVideo))) {
                   if (number_of_icons &lt; 10) {
                       videoIcon = null;
                       ++number_of_icons;
                       l_iconType = 22;
                   } else {
                       videoIcon = null;
                       l_iconType = 2;
                   }
                   this.displayEntries.add(new IconifiedTextSelected(
                           currentFile.getPath(),
                           videoIcon, false, false, l_iconType));
               }
           }
       }
    }

    private void getVideosFromDirectoryRecur(File _dir) {
       Drawable videoIcon = null;
       File[] files = _dir.listFiles();
       int l_iconType = 2;
       if (files == null) {
           return;
       }
       for (File currentFile : files) {
           if (currentFile.isDirectory()) {
               getVideosFromDirectoryRecur(currentFile);
               continue;
           } else {
               String l_filename = currentFile.getName();
               //if it&#39;s an image file
               if (checkEndsWithInStringArray(l_filename,
                       getResources().getStringArray(R.array.fileEndingVideo))) {
                   if (number_of_icons &lt; 10) {
                       videoIcon = null;
                       ++number_of_icons;
                       l_iconType = 22;
                   } else {
                       videoIcon = null;
                       l_iconType = 2;
                   }
                   this.displayEntries.add(new IconifiedTextSelected(
                           currentFile.getPath(),
                           videoIcon, false, false, l_iconType));
               }
           }
       }
    }

    private void getVideosFromGallery() {
       Drawable videoIcon = null;
       Uri uri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
       String[] projection = {MediaStore.Video.Media.DATA};
       Cursor l_cursor = this.managedQuery(uri, projection, null, null, null);
       int videoNameColumnIndex;
       String videoFilename;
       File videoFile;
       int l_iconType = 2;
       if (l_cursor!=null) {
           if (l_cursor.moveToFirst()) {
               do {
                   videoNameColumnIndex = l_cursor.getColumnIndexOrThrow(
                           MediaStore.Images.Media.DATA);
                   videoFilename = l_cursor.getString(videoNameColumnIndex);
                   videoFile = new File(videoFilename);
                   if (!videoFile.exists()) {
                       continue;
                   }
                   if (number_of_icons &lt;= 10) {
                       videoIcon = null;
                       ++number_of_icons;
                       l_iconType = 22;
                   } else {
                       videoIcon = null;
                       l_iconType = 2;
                   }
                   this.displayEntries.add(new IconifiedTextSelected(
                           videoFile.getAbsolutePath(),
                           videoIcon, false, false, l_iconType));
               } while (l_cursor.moveToNext());
           }
       }
       if (l_cursor!=null) {
           l_cursor.close();
       }
    }

    private boolean checkEndsWithInStringArray(String checkItsEnd,
           String[] fileEndings){
       for(String aEnd : fileEndings){
           if(checkItsEnd.endsWith(aEnd))
               return true;
       }
       return false;
    }

    private class LoadVideoTask extends AsyncTask {
       @Override
       protected void onPreExecute() {
           System.gc();
           displayEntries.clear();
           showDialog(DIALOG_LOAD_MEDIA);
       }
       @Override
       protected Void doInBackground(String... params) {
           File l_root = new File(params[0]);
           if (l_root.isDirectory()) {
               number_of_icons = 0;
               currentDirectory = l_root;
               if (media_browser_load_option == 0) {
                   //list all videos in the root directory without going into sub folder
                   getVideosFromDirectoryNonRecurAddParent(l_root);
                   getVideosFromDirectoryNonRecur(l_root);
               } else if (media_browser_load_option == 1) {
                   //list all videos in the root folder recursively
                   getVideosFromDirectoryRecur(l_root);
               } else if (media_browser_load_option == 2) {
                   //list all videos in the gallery
                   getVideosFromGallery();
               }
           }
           return null;
       }
       @Override
       protected void onPostExecute(Void n) {
           refreshUI();
           dismissDialog(DIALOG_LOAD_MEDIA);
       }
    }

    /**
    * UI: this part of the source code deals with UI
    */
    //bottom menu
    private int currentFocusedBtn = 1;
    private Button btn_bottommenu1;
    private Button btn_bottommenu2;
    private Button btn_bottommenu3;
    //private Button btn_bottommenu4;
    //title bar
    private TextView text_titlebar_text;

    private void initUI() {
       this.requestWindowFeature(Window.FEATURE_NO_TITLE);
       this.setContentView(R.layout.video_browser);
       //title bar
       text_titlebar_text = (TextView) findViewById(R.id.titlebar_text);
       text_titlebar_text.setText("Click a video to display info");

       //bottom menu
       int l_btnWidth = this.getWindowManager().getDefaultDisplay().getWidth()/4;
       btn_bottommenu1 = (Button) findViewById(R.id.video_browser_btn1);
       //btn_bottommenu1 = (ActionMenuButton) findViewById(R.id.main_topsecretimport_btn1);
       btn_bottommenu1.setWidth(l_btnWidth);
       btn_bottommenu1.setOnClickListener(new View.OnClickListener() {
           public void onClick(View v) {
               btn_bottommenu1.setEnabled(false);
               btn_bottommenu2.setEnabled(true);
               btn_bottommenu3.setEnabled(true);
               currentFocusedBtn = 1;
               last_list_view_pos = 0;
               media_browser_load_option = 2;
               last_media_browser_load_option = media_browser_load_option;
               loadVideosFromDirectory("/sdcard/");
           }
       });
       btn_bottommenu2 = (Button) findViewById(R.id.video_browser_btn2);
       btn_bottommenu2.setWidth(l_btnWidth);
       btn_bottommenu2.setOnClickListener(new View.OnClickListener() {
           public void onClick(View v) {
               btn_bottommenu1.setEnabled(true);
               btn_bottommenu2.setEnabled(false);
               btn_bottommenu3.setEnabled(true);
               currentFocusedBtn = 2;
               last_list_view_pos = 0;
               media_browser_load_option = 0;
               last_media_browser_load_option = media_browser_load_option;
               loadVideosFromDirectory("/sdcard/");
           }
       });
       btn_bottommenu3 = (Button) findViewById(R.id.video_browser_btn3);
       btn_bottommenu3.setWidth(l_btnWidth);
       btn_bottommenu3.setOnClickListener(new View.OnClickListener() {
           public void onClick(View v) {
               btn_bottommenu1.setEnabled(true);
               btn_bottommenu2.setEnabled(true);
               btn_bottommenu3.setEnabled(false);
               currentFocusedBtn = 3;
               last_list_view_pos = 0;
               media_browser_load_option = 1;
               last_media_browser_load_option = media_browser_load_option;
               loadVideosFromDirectory("/sdcard/");
           }
       });
       media_browser_load_option = last_media_browser_load_option;
       if (media_browser_load_option==2) {
           btn_bottommenu1.setEnabled(false);
       } else if (media_browser_load_option==0) {
           btn_bottommenu2.setEnabled(false);
       } else if (media_browser_load_option==1){
           btn_bottommenu3.setEnabled(false);
       }
       loadVideosFromDirectory("/sdcard/");
    }
    //refresh the UI when the directoryEntries changes
    private static int last_list_view_pos = 0;
    public void refreshUI() {
       int l_btnWidth = this.getWindowManager().getDefaultDisplay().getWidth()/4;
       btn_bottommenu1.setWidth(l_btnWidth);
       btn_bottommenu2.setWidth(l_btnWidth);
       btn_bottommenu3.setWidth(l_btnWidth);
       //btn_bottommenu4.setWidth(l_btnWidth);

       SlowAdapter itla = new SlowAdapter(this);
       itla.setListItems(this.displayEntries);    
       this.setListAdapter(itla);
       getListView().setOnScrollListener(this);
       int l_size = this.displayEntries.size();
       if (l_size > 50) {
           getListView().setFastScrollEnabled(true);
       } else {
           getListView().setFastScrollEnabled(false);
       }
       if (l_size > 0) {
           if (last_list_view_pos &lt; l_size) {
               getListView().setSelection(last_list_view_pos);
           } else {
               getListView().setSelection(l_size-1);
           }
       }
       registerForContextMenu(getListView());
    }

    @Override
    public void onConfigurationChanged (Configuration newConfig) {
       super.onConfigurationChanged(newConfig);
       refreshUI();
    }

    static final int DIALOG_LOAD_MEDIA = 1;
    static final int DIALOG_HELP = 2;
    @Override
    protected Dialog onCreateDialog(int id) {
       switch(id) {
       case DIALOG_LOAD_MEDIA:
           ProgressDialog dialog = new ProgressDialog(this);
           dialog.setTitle("Load Files");
           dialog.setMessage("Please wait while loading...");
           dialog.setIndeterminate(true);
           dialog.setCancelable(true);
           return dialog;
       default:
           return null;
       }
    }
    /**
    * scroll events methods: this part of the source code contain the control source code
    * for handling scroll events
    */
    private boolean mBusy = false;
    private void disableButtons() {
       btn_bottommenu1.setEnabled(false);
       btn_bottommenu2.setEnabled(false);
       btn_bottommenu3.setEnabled(false);
    }

    private void enableButtons() {
       if (currentFocusedBtn!=1) {
           btn_bottommenu1.setEnabled(true);
       }
       if (currentFocusedBtn!=2) {
           btn_bottommenu2.setEnabled(true);
       }
       if (currentFocusedBtn!=3) {
           btn_bottommenu3.setEnabled(true);
       }
    }
    public void onScroll(AbsListView view, int firstVisibleItem,
           int visibleItemCount, int totalItemCount) {
       last_list_view_pos = view.getFirstVisiblePosition();
    }

    //private boolean mSaveMemory = false;
    public void onScrollStateChanged(AbsListView view, int scrollState) {      
       switch (scrollState) {
       case OnScrollListener.SCROLL_STATE_IDLE:
           enableButtons();
           mBusy = false;
           int first = view.getFirstVisiblePosition();
           int count = view.getChildCount();
           int l_releaseTarget;
           for (int i=0; i/if outofmemory, we try to clean up 10 view image resources,
                       //and try again
                       for (int j = 0; j &lt; 10; ++j) {
                           l_releaseTarget = first - count - j;
                           if (l_releaseTarget > 0) {
                               IconifiedTextSelected l_its = displayEntries.get(l_releaseTarget);
                               IconifiedTextSelectedView l_itsv = (IconifiedTextSelectedView)
                                   this.getListView().getChildAt(l_releaseTarget);
                               if (l_itsv!=null) {
                                   l_itsv.setIcon(null);
                               }
                               if (l_its != null) {
                                   Drawable l_dr = l_its.getIcon();
                                   l_its.setIcon(null);
                                   if (l_dr != null) {
                                       l_dr.setCallback(null);
                                       l_dr = null;
                                   }
                               }
                           }
                       }
                       System.gc();
                       //after clean up, we try again
                       if (l_type == 1) {
                           l_icon = null;
                       } else if (l_type == 2) {
                           l_icon = null;
                       }
                   }
                   this.displayEntries.get(first+i).setIcon(l_icon);
                   if (l_icon != null) {
                       t.setIcon(l_icon);
                       t.setTag(null);
                   }
               }
           }
           //System.gc();
           break;
       case OnScrollListener.SCROLL_STATE_TOUCH_SCROLL:
           disableButtons();
           mBusy = true;
           break;
       case OnScrollListener.SCROLL_STATE_FLING:
           disableButtons();
           mBusy = true;
           break;
       }
    }

    /**
    * List item click action
    */
    private File currentFile;
    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
       super.onListItemClick(l, v, position, id);
       last_list_view_pos = position;
       String selectedFileOrDirName = this.displayEntries.get((int)id).getText();
       if (selectedFileOrDirName.equals(upOneLevel)) {
           if (this.currentDirectory.getParent()!=null) {
               last_list_view_pos = 0;
               browseTo(this.currentDirectory.getParentFile());
           }
       } else {
           File l_clickedFile = new File(this.displayEntries.get((int)id).getText());
           if (l_clickedFile != null) {
               if (l_clickedFile.isDirectory()) {
                   last_list_view_pos = 0;
                   browseTo(l_clickedFile);
               } else {
                   showVideoInfo(l_clickedFile);
               }
           }
       }
    }

    private void browseTo(final File _dir) {
       if (_dir.isDirectory()) {
           this.currentDirectory = _dir;
           loadVideosFromDirectory(_dir.getAbsolutePath());
       }
    }

    /**
    * Slow adapter: this part of the code implements the list adapter
    * Will not bind views while the list is scrolling
    */
    private class SlowAdapter extends BaseAdapter {
       /** Remember our context so we can use it when constructing views. */
       private Context mContext;

       private List<iconifiedtextselected> mItems = new ArrayList<iconifiedtextselected>();

       public SlowAdapter(Context context) {
           mContext = context;
       }

       public void setListItems(List<iconifiedtextselected> lit)
       { mItems = lit; }

       /** @return The number of items in the */
       public int getCount() { return mItems.size(); }

       public Object getItem(int position)
       { return mItems.get(position); }

       /** Use the array index as a unique id. */
       public long getItemId(int position) {
           return position;
       }

       /** @param convertView The old view to overwrite, if one is passed
        * @returns a IconifiedTextSelectedView that holds wraps around an IconifiedText */
       public View getView(int position, View convertView, ViewGroup parent) {
           IconifiedTextSelectedView btv;
           if (convertView == null) {
               btv = new IconifiedTextSelectedView(mContext, mItems.get(position));
           } else { // Reuse/Overwrite the View passed
               // We are assuming(!) that it is castable!
               btv = (IconifiedTextSelectedView) convertView;
               btv.setText(mItems.get(position).getText());
           }
           if (position==0) {
               if (VideoBrowser.self.media_browser_load_option==0) {
                   btv.setIcon(R.drawable.folderback);
               } else if (mItems.get(0).getIcon()!=null) {
                   btv.setIcon(mItems.get(position).getIcon());
               } else {
                   btv.setIcon(R.drawable.video);
               }
           }
           //in busy mode
           else if (mBusy){
               //if icon is NULL: the icon is not loaded yet; load default icon
               if (mItems.get(position).getIcon()==null) {
                   btv.setIcon(R.drawable.video);
                   //mark this view, indicates the icon is not loaded
                   btv.setTag(this);
               } else {
                   //if icon is not null, just display the icon
                   btv.setIcon(mItems.get(position).getIcon());
                   //mark this view, indicates the icon is loaded
                   btv.setTag(null);
               }
           } else {
               //if not busy
               Drawable d = mItems.get(position).getIcon();
               if (d == null) {
                   //icon is not loaded, load now
                   btv.setIcon(R.drawable.video);
                   btv.setTag(this);
               } else {
                   btv.setIcon(mItems.get(position).getIcon());
                   btv.setTag(null);
               }
           }
           return btv;
       }
    }
    </iconifiedtextselected></iconifiedtextselected></iconifiedtextselected></iconifiedtextselected></iconifiedtextselected></iconifiedtextselected></iconifiedtextselected>

    }

  • How would I assign multiple MMAP's from single file descriptor ?

    9 juin 2011, par Alex Stevens

    So, for my final year project, I'm using Video4Linux2 to pull YUV420 images from a camera, parse them through to x264 (which uses these images natively), and then send the encoded stream via Live555 to an RTP/RTCP compliant video player on a client over a wireless network. All of this I'm trying to do in real-time, so there'll be a control algorithm, but that's not the scope of this question. All of this - except Live555 - is being written in C. Currently, I'm near the end of encoding the video, but want to improve performance.

    To say the least, I've hit a snag... I'm trying to avoid User Space Pointers for V4L2 and use mmap(). I'm encoding video, but since it's YUV420, I've been malloc'ing new memory to hold the Y', U and V planes in three different variables for x264 to read upon. I would like to keep these variables as pointers to an mmap'ed piece of memory.

    However, the V4L2 device has one single file descriptor for the buffered stream, and I need to split the stream into three mmap'ed variables adhering to the YUV420 standard, like so...

    buffers[n_buffers].y_plane = mmap(NULL, (2 * width * height) / 3,
                                       PROT_READ | PROT_WRITE, MAP_SHARED,
                                       fd, buf.m.offset);
    buffers[n_buffers].u_plane = mmap(NULL, width * height / 6,
                                       PROT_READ | PROT_WRITE, MAP_SHARED,
                                       fd, buf.m.offset +
                                       ((2 * width * height) / 3 + 1) /
                                       sysconf(_SC_PAGE_SIZE));
    buffers[n_buffers].v_plane = mmap(NULL, width * height / 6,
                                       PROT_READ | PROT_WRITE, MAP_SHARED,
                                       fd, buf.m.offset +
                                       ((2 * width * height) / 3 +
                                       width * height / 6 + 1) /
                                       sysconf(_SC_PAGE_SIZE));

    Where "width" and "height" is the resolution of the video (eg. 640x480).

    From what I understand... MMAP seeks through a file, kind of like this (pseudoish-code) :

    fd = v4l2_open(...);
    lseek(fd, buf.m.offset + (2 * width * height) / 3);
    read(fd, buffers[n_buffers].u_plane, width * height / 6);

    My code is located in a Launchpad Repo here (for more background) :
    http://bazaar.launchpad.net/ alex-stevens/+junk/spyPanda/files (Revision 11)

    And the YUV420 format can be seen clearly from this Wiki illustration : http://en.wikipedia.org/wiki/File:Yuv420.svg (I essentially want to split up the Y, U, and V bytes into each mmap'ed memory)

    Anyone care to explain a way to mmap three variables to memory from the one file descriptor, or why I went wrong ? Or even hint at a better idea to parse the YUV420 buffer to x264 ? :P

    Cheers ! ^^