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Subject: Re: question to all blind rockboxers

Re: question to all blind rockboxers

From: <chou.clement_at_gmail.com>
Date: Thu, 17 May 2007 16:03:39 -0700

Actually, just one minor correction if I may, Paul. The fourth whole on the
subpack as you described is not a line jack. Rather, it's not a line out
jack. It's actually a line in / out jack, ad I believe it can be changed via
the firmware and settings. The other jack that is right next to your usb is
actually a remote jack. And the slit's purpose is unknown right below the
headphone jack. Under the slit is actually a piece of plastic, which reveals
the USB 1.1 OTG port. If you feel carefully, you will feel something that is
not quite smooth. It should be noticible.. I Thought it was the internal
microphone, but you don't want to get that mistaken... that's where you said
it was. Just a few things I thought I would point out.

Best,
Clement.
----- Original Message -----
From: "Paul Erkens" <pjealt_at_xs4all.nl>
To: "Rockbox" <rockbox_at_cool.haxx.se>
Sent: Thursday, May 17, 2007 3:48 PM
Subject: question to all blind rockboxers

> Hi,
>
> Since I got my IAudio x5, I really had a whole bunch of stuff to learn. I
> was rather a novice. The information on the net aimed directly at blind
> people is there to some degree, and that's wonderful already. But it is
> not very extensive up till now.
> I'm writing a document right now, from which other blind folks can learn
> what I had to learn. I started writing this afternoon, and I'd like to
> know from you guys out here, if you think I should do it differently, keep
> going this way, or leave it altogether because I'm completely wrong.
>
> If any of you cares to take a look at my first attempts, I am pasting it
> below. If the reactions are okay and I can get it finished in the near
> future, I'm planning to send it off to the rockbox team, and see if they
> find it useful enough to place it on their site for other blind
> adventurous souls to use. Rockbox is made by very knowledgeable people,
> but introductory docs for the unknowing like myself, I haven't found so
> far. Would you as a blind reader find this a useful document? Especially
> the section describing the IAudio mp3 player itself.
>
> Comments welcome. It is my first attempt to write it, unfinished nor
> polished. I'm not a native English speaker. I just want to know if I'm on
> the right track to really make a difference when I get it done. I'd like
> to contribute my little bit.
> ---
> Guide for the blind: rockbox on your IAudio x5 mp3 player.
>
> Contents ideas:
> ========
> introduction
> What are we talking about?
> -walkmans and accessibility
> -what is mp3 really?
> Description of the IAudio x5
> Hearing the demos on the unit
> an explanation of firmware
> what is rockbox for us?
> How the speech system works
> About the files to download and what they do
>
> Introduction
>
> Welcome. This guide is intended for blind folks, wanting to have an
> accessible mp3 player. I am blind myself, and from the directions on the
> internet, I finally managed to get rockbox to work on my player. The
> information I needed was not bundled in one place, and most documents were
> very brief. Now that I have my own player going and now that I've seen how
> great rockbox just is for us once it's running, I want to share my
> knowledge and experience with you, so you don't have to invent the wheel
> again.
>
> In short, if you already know what an mp3 walkman is: with rockbox, you
> can now navigate almost all menus, configure almost all options and do
> almost anything a sighted user is capable of, using the display screen on
> the unit. New functions and possibilities are added constantly, and what
> you can't do today, may be possible next week. Rockbox makes your mp3
> player talk, so you will know what you are doing as you operate its
> controls. That is what rockbox is all about for blind people. A work in
> progress, already working on many different mp3 players, talking to you,
> and improving continuously.
>
> This is not a technical document, because I'm not technically inclined
> myself. I will explain what you are required to do, why you must do it,
> and in our case without vision: how it should be done.
>
> I can only describe the procedure for the IAudio x5 mp3 player. Other
> players, I don't have any experience with so far. If you have something
> other than the IAudio x5, this document will provide you with background
> information so you will understand what's up, but the specific
> installation details for other players than the IAudio x5 are not covered
> here.
>
> We will begin by providing you with some useful background information.
> Only read it if you're interested. We will discuss audio compression, and
> similar background topics. Then, we'll dive into describing the IAudio x5
> unit, showing you how to get started with rockbox.
>
> In many cases, I will refer to the IAudio x5 rockbox manual on the rockbox
> site. This document is an addition just to get you started; It's by no
> means a replacement for anything.
>
> If you have any suggestions for this document, please write me at
> pjealt_at_xs4all.nl. I can't provide support for general rockbox problems,
> because all I do is write and maintain this document. Please write me only
> if you think an important concept is missing from this document.
>
> What are we talking about?
> =====================
>
> So, what are we talking about in this document in the first place? Simply
> put: until rockbox came, we did not have good access to digital walkmans.
> But now we do. If you buy yourself an x5 walkman from IAudio, this
> document tells you how to set it up for yourself, so that it talks to you
> as you operate it.
>
> walkmans and accessibility
>
> If you like music, talking books, radio plays or other forms of recorded
> audio, it is great to have a mobile device, on which the audio you want to
> listen to is stored. When I was young, I used to have one of the first
> walkman players that could play cassette tapes. It weighed almost two
> American pounds, which is near to 1 kilo gram in European measurement. It
> required six pen light batteries, it had head phones attached, the
> batteries lasted less than two hours, and I was extremely proud to walk
> around with that brick. But after two months of intensive use, the tape
> started to slow down, the sound became bad and I did away with it finally.
> Not only had the player been expensive, but it wore out pretty quickly.
>
> These days, walkmans have improved dramatically. The music is no longer
> stored on cassette tapes but on different media. The modern media are
> digital in nature. How digital audio works exactly, falls outside the
> scope of this document. The advantage of using digitally stored audio in
> your walkman is however, that its sound quality is much better. Besides,
> it is now much easier to instantly play a song of your liking. You don't
> have to change tapes and cue back and forth, to find the song you want to
> hear. Instead, you navigate through your collection using a small display
> screen on the walkman, to find and play it.
>
> And here is our problem. If you can't read the display on the unit, you
> won't be able to access most of its functions and settings. These devices
> become more and more menu based, with logical categories in which you can
> find the option you want to tweak. Absolutely fabulous for sighted people,
> but by far not for us. You know how computers are made accessible though.
> The screen is read to us by an electronic voice, and because of that, we
> can navigate our files, do text processing and many other computer tasks,
> even including installing windows XP without sighted assistance. If you
> are determined, that is.
>
> Generally, most manufacturers of modern digital equipment don't really
> adapt their stuff such, that people with disabilities can make good use of
> them. We can get along some by memorizing key stroke sequences, but modern
> devices have become way too complex. This meant, that the pleasure of
> digital walkmans was only available for us if we didn't demand too much.
> You could buy yourself one, but only 20% or so of its functions that you
> payed for, will be usable for you.
>
> Well: no more. Thanks to the time and effort spent by the rockbox team, we
> now have the possibility to use these modern walkmans, and not just that.
> We can also make a well informed choice among the different models on
> which it runs. Rockbox won't work on all modern walkmans, but more are
> added over time and what these people have achieved so far, is impressive.
> Just take a look on the rockbox site, and see which mp3 walkmans are
> already currently supported. Go to your local dealer and get yourself one
> from that list.
>
> What is mp3 really?
>
> Next, we need to understand what mp3 really is. Mp3 is not a walkman, a
> player, nor a dvd feature. Mp3 is a file format. Let's see what this
> means.
>
> A file on your computer is something you will be familiar with. A file can
> contain a letter or other text, it could contain a picture, and likewise a
> file on your computer can also contain audio. If you play an audio file on
> your computer, you will hear the sound from the file out of your pc
> speakers. There are a number of different audio file types that are
> currently used throughout the world. Simply put, there are only two basic
> types of audio files: compressed, and uncompressed. Let's talk about what
> this means.
>
> On a regular audio cd, audio is stored plainly. The original sound has
> been encoded into small groups of digits: ones and zeroes, and these are
> stored on the compact disk. It is possible to have your computer's cd or
> dvd drive read that digital audio information off the cd, and storing it
> in regular computer files on your hard drive. This process is called
> "ripping a cd", i.e. copying the audio data over from the cd on to your
> computer's hard disk.
>
> However, a simple cd contains an enormous amount of data. If we speak in
> megabytes, a cd contains roughly 800 megabytes worth of audio data. Once
> you have the contents of your cd inside your computer, you can hook up
> your digital walkman to it, and then transfer those files.
>
> You should be aware however, that the storage capacity of your digital
> walkman is usually quite limited, if you compare it to the capacity of
> your computer's hard disk. Audio, in its plain form, is quite big. When
> digital walkmans first came to market, we had devices that could contain
> 32 megabytes max. Now if you realise that in plain storage format, an
> audio file eats up 10 megabytes for every minute of music, you will
> understand that in these players, there was only room for a song of about
> 3 minutes in length, and obviously, you want more music in your walkman
> than just one little song.
>
> Two things have been done to overcome this problem. First, a group of
> clever people invented a method of reducing the size of regular audio
> files down to a tenth of what they used to be. This is what is now called:
> audio compression. It essentially just means, bringing down the size of
> the audio file whilst retaining the maximum possible sound quality. The
> human ear is not very accurate, compared to a computer. What audio
> compression does, is throw away those parts of the audio that we are not
> likely to perceive. The more of the audio you throw away, the smaller the
> resulting file can be.
>
> And now we have something to work with. On a windows machine, a file
> containing plain audio is called a wave file, usually having a period and
> the letters w a v at the end of its name. Wave files can be quite big.
> Usually, they are uncompressed. Plain.
>
> On the other hand, the most common way of compressing audio these days, is
> called mp3. So the word mp3 just refers to the way the audio itself is
> compressed. Compressed audio files usually have a dot and the letters m p
> 3 at the end of their name.
>
> To summarize: if, for example, you see a file called song.wav on your
> computer, you know that it usually is an uncompressed audio file, because
> of the dot wav at the end. If you encounter something like song.mp3 or
> today.mp3, you know that it is compressed audio, because of the dot m p 3
> at the end of the file's name. This is only a rule of thumb, because we
> did not take into account the fact that even wave files can be compressed,
> and still be called .wav. But let's not get lost in the details.
>
> We mentioned before, that mp3 reduces file sizes by throwing away
> frequencies in the audio you are not likely to hear. The better
> compression you want to achieve, the more audio you need to throw away. If
> you keep going, you will get to a point where the audio damage becomes
> perceptible. You will hear it. So there's always a tradeoff between
> filesize and quality. In mp3 jargon, the compression factor that
> determines both the final file size and also the resulting sound quality,
> is called the mp3 bitrate. If you are going to create your own mp3 files
> from cd's you have, then the bitrate is something you can configure.
> Bitrate and compression factor refers to the same thing, as far as mp3 is
> concerned.
>
> A song in wave format containing 3 minutes worth of cd quality audio,
> would become 30 megabytes in size on disk. If you make an mp3 out of this,
> then you will still have a file of reasonable quality if you compress it
> down to a tenth of its original size. One song in mp3 format could then
> become 3 megabytes rather than 30, and still sound quite okay. And if you
> only have 32 megabytes of storage available on your player, that's quite
> an improvement. You can now store ten songs, rather than just one in
> uncompressed format. In other words: audio used to be way to large to
> handle. Mp3 has given us a solution, by drastically cutting down the file
> size of our digital audio.
>
> Old mp3 players were equipped with a memory chip and these devices are
> still widely used, except that the memory capacity has grown enormously,
> which is the second improvement over the first digital mp3 players with
> limited capacity. Mp3 walkmans in the form of a small plastic stick can
> well contain 4000 megabytes, 4 gig, which is really quite something. And
> that's not all.
>
> Modern mp3 walkmans don't store their audio in a memory chip. Instead,
> they have a tiny hard disk built in to them. This leads to walkmans with
> great storage capabilities. 40 to 60 gigabytes (being 40000 to 60000
> megabytes) is no exception these days, giving you ample space for
> thousands of songs.
>
> There are many brands to choose from, if you want such a walkman or mp3
> player. Before purchasing one, you need to decide for yourself how much
> you are going to store on it. If a couple of gigabytes is enough, a player
> with a memory chip will suffice. But if you want 40, 60 or 80 gigabytes
> worth of music, then you should buy a player that has a hard drive built
> in.
>
> Description of the IAudio x5
> ============================
>
> I chose the Cowon x5, which is an mp3 walkman manufactured by a company
> called IAudio. This player comes in a few flavours. The things that make
> the difference between the various models are the capacity of the hard
> disk inside it, and the battery life. If you have an x5l, then the l
> stands for long battery life. The player is thicker because of the bigger
> battery. Mine has a normal battery life, it is not the thicker one, and
> the hard disk can contain up to 60 gigabytes worth of data.
>
> The player is as small as a packet of cigarets. It is a metal casing that
> feels very solid. It has only a few buttons, and a joy stick. You can buy
> an optional leather protection for it, and even when the player is inside
> the protection leather, you can operate it well. Let's describe the unit,
> so you will know what is where.
>
> Put the player on a flat surface in front of you. If you feel its roof and
> all you encounter is four tiny dots, one on each corner, then you now have
> the unit upside down. The side that is now facing the table, should face
> the sky. If however, you now feel a very smooth rectangle and a button
> inside a circle, then the unit is already half way in the correct
> position.
>
> Now, we must make sure that the player is in the same position as I have
> it here, in order for the side descriptions to match. As you can feel, the
> roof of the player consists of two distinct levels. A thick and a thin
> part. Now, the thicker part that feels all smooth, is the visual display
> screen. Rotate the unit, so the display is at the top of the unit,
> furthest away from you. The bottom part of your x5 contains this little
> knob inside a small circle. This is your joy stick, and we will discuss
> what it does later on. Now, we can describe the four sides of your x5 in
> succession.
>
> The left side contains your head phone connector, and a slit to make the
> player act as a USB host. The top has a light, the right has power/hold,
> record, play, microphone and reset hole, while the bottom has the subpack
> connector. Okay, slowly this time.
>
> We'll start with the left side. Sliding your finger from top to bottom, so
> from the top left towards the bottom left corner, the first thing you
> encounter is a tiny round hole for your head phones.
>
> A little further down is a slit, which is probably a connector you won't
> be using very often. Sighted people can use it to have the x5 act as a USB
> host, so they can connect their digital camera to the x5, and transfer the
> pictures they have in the camera, over to the x5. This way, the camera's
> internal memory card can be wiped out and the photo shooting can continue
> again. Rockbox may utilize this connector for other purposes, but to my
> current knowledge, it is of no use for us right now. The rest of the left
> side does not contain any extra connectors or controls.
>
> The top side, running your finger across, reveals no more than a visual
> indicator, showing wether the x5 is currently charging. If you're totally
> blind, this is of no use to you.
>
> Then the right side of the player. Again, slide your finger from top to
> bottom, from upper right to bottom right. First, you will find a switch
> that you can slide up or down. Initially, it is always in its middle
> position. This switch has many functions, but to begin with, remember this
> as your power switch to turn the x5 on and off. Push upwards and let go.
> Then listen closely if you hear the hard disk spin up. If not, just try
> again until the device switches itself on. After a few seconds, the hard
> disk will shut off again, but the device is still awake. Making the hard
> drive spin, takes power from the battery, so as soon as the x5 is done
> reading and writing to the disk, it stops to save power. To turn the x5
> off again, do the same thing. Push the switch up and let go, until the
> device switches off.
>
> This power switch has yet another function. If you slide it down, it won't
> flick back to its original position in the middle. After sliding the
> switch down, it just stays there. In this position, the unit is on hold.
> This means that none of the other buttons perform any function. Very handy
> if you want to tuck away the x5 somewhere in a pocket, and you want to be
> sure the battery won't go flat by accidentally starting playback without
> head phones, which obviously wastes battery life.
>
> Note: you can test wether the device is on or off, by making sure this
> switch is in the middle so that the x5 accepts key strokes, and then
> attempting to play, see below. If it playes, then the unit is still on.
> This is no guarantee that the player is on or off indeed, but is is
> something to begin with.
>
> Further down the right side, just below the power/hold switch, you will
> find two rectangular buttons. The top one is rec, the bottom one is play.
> More on these later.
>
> Further down, you may feel a couple of teeny weeny holes in the metal
> strip. The top hole is the internal microphone, and the bottom hole is
> reset. To reset the unit, you can stick a long, thin object into it, which
> will touch the hidden reset button. Use it in case your firmware crashes
> and you want to start over.
>
> Finally, the bottom side. In the middle, this side contains a metal slit
> that almost feels like a slot for an sd memory card, but that is not what
> it's meant for. This is the connector for the subpack, being a small
> plastic device that you got together with your x5. One side of the subpack
> plugs into the x5, and on the other side of the subpack which, when
> connected, is now the bottom side of the device, you will find a number of
> connectors.
>
> From left to right, the connectors on the subpack are as follows: AC, USB,
> line in and line out. The last two I am not sure about. They may be line
> out and then line in.
>
> Hearing the demos on the unit
> =============================
>
> If you are like me, before doing anything else, you will want to hear what
> your x5 really sounds like. If all goes well, you won't be disappointed.
> Wear your ear phones and plug the cable into the socket on the top left
> side of your x5, as described earlier. Then, turn the unit on as
> described. When the hard disk spins up, wait for it to spin down again and
> then press play. If you don't hear anything, try play again. I heard music
> immediately and it sounded just awesome. Not that I love the demo itself,
> but the quality is pristine.
>
> Now, feel your joy stick. This joy stick can be moved in all four
> directions: east, west, north and south, or three o'clock, nine o'clock,
> twelve o'clock and six o'clock if you prefer. Place your finger south of
> the joy stick, six o'clock, and push upward, away from you. The volume
> will increase. Likewise, place your finger north of the stick and gently
> pull the stick towards you, down. The volume will decrease.
>
> Pushing right will move to the next file on the player. Moving left first
> goes to the start of the current song or, when done in the first few
> seconds of the track, moves you to the start of the previous track.
>
> You will notice that the demos more or less all sound the same. There's
> video together with the audio, but just forget about that because it's
> useless to us.
>
> What is firmware?
>
> You may wonder, how your mp3 player is capable of playing digital music.
> Your pc has a micro processor to read from disk, process sound, create
> video etc. But what about your mp3 player? Well, your x5 is a computer on
> its own. It too has its own memory, its own hard disk and a micro
> processor. The operating system is usually stored on the hard disk. In a
> pc, that is usually windows (sorry linux lovers, just by means of saying),
> and on mp3 players, the operating system is going to be rockbox.
>
> Now to understand what we are actually changing to make the player go
> rockbox, we need to go over some concepts first. You know that your
> computer has a processor and that it has memory too. If you turn the pc
> on, it loads its operating system from hard disk, and then waits for you
> to do something with it. But let me ask you. How does your pc know that
> the operating system to load is stored on hard disk? You know that the
> computer can only do something if it has software that tells it what to
> do, and the operating system is exactly the piece of software to do that.
> But, when you first turn on your computer, the operating system still
> needs to be loaded from hard disk first. So, how can the computer know
> how to perform its very first steps, if the operating system has not been
> loaded yet? The computer tests its memory for errors right after you turn
> it on, but at that time, the hard disk has not even been touched to start
> loading the operating system. What makes the computer perform its startup
> tasks?
>
> The answer is: the bios. Bios, b i o s, stands for basic input output
> system. It's a small piece of software, not stored on a hard disk, but on
> a tiny chip somewhere on your motherboard, deep down inside your pc case.
> When you turn on your pc, what happens is that the bios first checks to
> see if all hardware is connected properly, and the bios then takes care of
> loading the operating system, windows. The bios only knows a few very
> basic functions to communicate with the hardware, enough to get the
> computer started. The operating system does the rest.
>
> The same goes for your mp3 player, your x5. When you turn it on, the first
> thing that happens is that the microprocessor starts running the program
> code, stored in the player's rom memory. After initializing the hardware,
> this code is responsible for loading the rest of the operating system from
> the hard disk.
>
> Because software is something created by humans, it can always contain
> errors, called bugs. Every now and then, computer manufacturers release
> new versions of this code on the internet. But as I said, bios code in a
> pc is stored on a chip inside the computer, not on the hard disk. Well, it
> is easy to download a new version of a certain file, on to your computer's
> hard drive. But how would you reprogram the contents of a special bios
> chip, deep inside your computer? Luckily, you don't need to worry about
> it, because the computer has a mechanism to do this for you. If you want
> to update your computer's bios, for example when USB functions strangely
> and you read on the manufacturer's site that the latest bios version fixes
> this, then you can simply download a file containing the new code. You
> then put this file in a special location, turn your machine off and on,
> tell it to look for the new bios file, and let it reprogram its own bios
> chip as you wait a few seconds.
>
> Now. Your x5 also has sort of a bios, and an operating system. When you
> first buy your x5, it's got startup code and an operating system inside
> it, provided by Iaudio. The code programmed into the rom memory of the
> player itself, is called the firmware. According to wikipedia, firmware is
> embedded software, but this can be a confusing and difficult term.
> Firmware in your x5 is like the bios code in your pc. It runs when you
> start the player, and makes the player react to your key presses and joy
> stick movements.
>
> However, this initially provided operating system from IAudio is not blind
> friendly at all. It does not speak, and you'll have a hard time
> remembering how many times to push your joy stick left, down, right etc,
> in order to get to a certain function.
>
> What rockbox is, is a complete replacement for the player's internal
> operating system. From the ground up, it has built in support for speech,
> so that we can use it as well. Part of rockbox must live inside the
> player's rom memory, and part of rockbox resides on the hard drive.
>
> So we need to get rid of the original IAudio operating system and startup
> code in our x5, and replace it with startup code and the operating system
> from rockbox. There are two separate processes to carry out.
>
> First, we need to put the disk part of rockbox onto the hard drive of our
> player. Next, we need to replace the boot code, so that the player knows
> how to load rockbox when we turn it on. A property of this x5 player is,
> that the original firmware can not continue to exist in the player after
> rockbox has been installed. On other players, at startup, you can choose
> to either run the IAudio firmware or the rockbox firmware. On our x5, this
> is not possible. Once you install rockbox, you loose your original
> firmware. No problem, because rockbox is better for us than Iaudio's
> firmware.
>
> Which files to get?
>
> Everything you need can be downloaded off the internet, from
> www.rockbox.org. For blind people using screen reading programs to access
> the information on the computer screen, this site is not easy to work
> with. If you need to, ask some sighted assistance if you can find someone
> willing to help you some. It's up to you to know what to get and where to
> look for it. You don't want to frustrate your helper by leaving it up to
> them to hunt for something they haven't read or learnt about.
>
>
Received on 2007-05-18


Page was last modified "Jan 10 2012" The Rockbox Crew
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