changeset 684:57020131563a

More changes to paper

--- a/docs/SMC15/smc2015template.tex	Mon Apr 20 19:01:39 2015 +0100
+++ b/docs/SMC15/smc2015template.tex	Tue Apr 21 12:56:54 2015 +0100
@@ -162,7 +162,7 @@
 [Previously, due to limited functionality of HTML, ..., it was not possible to design this type of interfaces with such high quality audio... ]
 
 
-\section{Design considerations}\label{sec:designconsiderations}
+%\section{Design considerations}\label{sec:designconsiderations} % not necessary? with next (/previous) section?
 
 We present a browser-based perceptual evaluation tool for audio that ... \\
 
@@ -176,15 +176,15 @@
 
 %section with overview of the structure of the input and output files, perhaps with graph or table
 
-The tool runs entirely inside the browser through the new HTML5 Web Audio API. The API is supported by most major web browsers (except Internet Explorer) and allows for constructing a chain of audio processing elements to produce a high quality, real time signal process to manipulate audio streams. The API supports multi-channel processing and has an accurate playback timer for precise scheduled playback control. The Web Audio API is controlled through the browser JavaScript and is therefore highly controllable. The Web Audio API processing is all controlled in a separate thread to the main JavaScript thread, meaning there is no blocking due to real time processing. 
+The tool runs entirely inside the browser through the new HTML5 Web Audio API. The API is supported by most major web browsers (with the exception of Internet Explorer) and allows for constructing a chain of audio processing elements to produce a high quality, real time signal process to manipulate audio streams. The API supports multi-channel processing and has an accurate playback timer for precise scheduled playback control. The Web Audio API is controlled through the browser JavaScript and is therefore highly controllable. The Web Audio API processing is all controlled in a separate thread to the main JavaScript thread, meaning there is no blocking due to real time processing. 
 
 \subsection{Interface}\label{sec:interface} %elsewhere?
 
-[Like \cite{deman2014b}, but others possible]
+At this point, we have implemented the interface of the MATLAB-based APE Perceptual Evaluation for Audio toolbox \cite{deman2014b}, which shows one marker for each simultaneously evaluated audio fragment on one or more horizontal axes (to rate/rank the respective fragments), as well as a comment box for every marker, and one extra text box for extra comments. See \ref{fig:interface} for an example of the interface, with 10 fragments and one axis. However, the back end of this test environment allows for many more established and novel interfaces for listening tests, particularly ones where the subject only assesses audio without manipulating it (i.e. method of adjustment, which would require additional features to be implemented). 
 
 \begin{figure*}[htbp]
 \begin{center}
-\includegraphics[width=\textwidth]{interface.png}
+\includegraphics[width=0.9\textwidth]{interface.png}
 \caption{Example of interface, with 1 axis and 10 fragments}
 \label{fig:interface}
 \end{center}
@@ -196,39 +196,71 @@
 
 The web tool itself is split into several files to operate:
 \begin{itemize}
-\item \texttt{apeTool.html}: The main index file to load the scripts, this is the file the browser must request to load
-\item \texttt{core.js}: Contains functions and objects to manage the audio control, audio objects for testing and loading of files
+\item \texttt{apeTool.html}: The main index file to load the scripts, this is the file the browser must request to load. 
+\item \texttt{core.js}: Contains functions and objects to manage the audio control, audio objects for testing and loading of files. 
 \item \texttt{ape.js}: Parses setup files to create the interface as instructed, following the same style chain as the MATLAB APE Tool \cite{deman2014b}.
 \end{itemize}
 
-The HTML file loads the core.js file with it along with a few other ancillary files (such as the jQuery JavaScript extensions), the browser JavaScript begins to execute the on page instructions, which gives the URL of the test setup XML document (outlined in the next section). The core.js parses this document and executes the function in \texttt{ape.js} to build the web page with the given audio files. The reason for separating these two files is to allow for further interface designs (such as MUSHRA \cite{mushra} or A-B tests \cite{bech}) to be used, which would still require the same underlying core functions outlined in \texttt{core.js}.
+The HTML file loads the \texttt{core.js} file with it along with a few other ancillary files (such as the jQuery JavaScript extensions), at which point the browser JavaScript begins to execute the on-page instructions, which gives the URL of the test setup XML document (outlined in the next section). \texttt{core.js} parses this document and executes the function in \texttt{ape.js} to build the web page with the given audio files. The reason for separating these two files is to allow for further interface designs (such as MUSHRA \cite{mushra} or A-B tests \cite{bech}) to be used, which would still require the same underlying core functions outlined in \texttt{core.js}, see also Section \ref{sec:interface}.
 
-The \texttt{ape.js} file has only two main functions: \textit{loadInterface(xmlDoc)} and \textit{interfaceXMLSave()}. The first function is called to build the interface once the setup document has been loaded. This includes creating the slider interface to rate the tracks and creating the comment boxes bellow. The bars in the slider ranking at the top of the page are randomly spaced. It also instructs the audio engine in the \texttt{core.js} to create the audio objects. The audio objects are custom built audio nodes built on the web audio API. They consist of a \textit{bufferSourceNode} (a node which holds a buffer of audio samples for playback) and a \textit{gainNode}. These are then connected to the \textit{audioEngine} (itself a custom web audio node) containing a \textit{gainNode} (where the various Audio Objects connect to) for summation before passing the output to the destination Node, a fixed node created where the browser then passes the audio information to the system sound device.
+The \texttt{ape.js} file has only two main functions: \textit{loadInterface(xmlDoc)} and \textit{interfaceXMLSave()}. The first function is called to build the interface once the setup document has been loaded. This includes creating the slider interface to rate the tracks, and creating the comment boxes below it. The markers on the slider at the top of the page are positioned randomly, to minimise the bias that may be introduced when the initial positions are near the beginning, end or middle of the slider. While another approach is to place the markers outside of the slider bar at first and have the subject drag them in, the authors believe this doesn't encourage careful consideration and comparison of the different fragments as the implicit goal of the test becomes to audition and drag each fragment in just once, rather than to compare all fragments rigorously. 
+\texttt{ape.js} also instructs the audio engine in \texttt{core.js} to create the audio objects. The audio objects are custom built audio nodes built on the Web Audio API. % 'built' twice?
+They consist of a \textit{bufferSourceNode} (a node which holds a buffer of audio samples for playback) and a \textit{gainNode}. These are then connected to the \textit{audioEngine} (itself a custom web audio node) containing a \textit{gainNode} (where the various Audio Objects connect to) for summation before passing the output to the \textit{destinationNode}, a fixed node created where %through which?
+the browser then passes the audio information to the system sound device. 
+% audio object/audioObject/Audio Object: consistency?
 
-When an \textit{audioObject} is created, the URL of the audio sample to load is given to it. This is downloaded into the browser asynchronously using the \textit{XMLHttpRequest} object. This allows for downloading of any file into the JavaScript environment for further processing. It is particularly useful for the Web Audio API because it supports downloading of files in their binary form, allowing a perfect copy. Once the asynchronous download is complete, the file is then decoded using the Web Audio API offline decoder. This uses the browser available decoding schemes to decode the audio files into raw float32 arrays, which are in-turn passed to the relevant audioObject bufferSourceNode for playback.
+When an \textit{audioObject} is created, it is given the URL of the audio sample to load. This is downloaded into the browser asynchronously using the \textit{XMLHttpRequest} object. This allows for downloading of any file into the JavaScript environment for further processing. It is particularly useful for the Web Audio API because it supports downloading of files in their binary form, allowing a perfect copy. % don't quite understand this
+Once the asynchronous download is complete, the file is then decoded using the Web Audio API offline decoder. This uses the browser's %browser's? browser-available? available in the browser?
+ available decoding schemes to decode the audio files into raw float32 arrays, which are in turn passed to the relevant audioObject \textit{bufferSourceNode} for playback.
 
-Browsers support various audio file formats and are not consistent in any format. One sure format that all browsers support is the WAV format. Although not a compact, web friendly format, most transport systems are of a high enough bandwidth this should not be a problem. However one problem is that of sample rate. On loading, the browser uses the sample rate assigned by the system sound device. The browser does not have the ability to request a different sound rate. Therefore the default operation when an audio file is loaded with a different sample rate to that of the system is to convert the sample rate. To provide a check for this, the desired sample rate can be supplied with the setup XML and checked against. If the sample rates do not match, a browser alert window is shown asking for the sample rate to be correctly adjusted. This happens before any loading or decoding of audio files. Only once the sample rates match will the system actually fetch any files, keeping down requests for the larger files until they are actually needed.
+% GENERAL QUESTION: would it be hard to support more file types? If so, I think it's much nicer to say 'at the moment we allow ... and ... and ... files'
+Browsers support various audio file formats and are not consistent in any format. % 'not consistent in any format'? What do you mean exactly?
+However, all browsers support the WAV format. Although not a compact, web friendly format, most transport systems are of a high enough bandwidth this should not be a problem. 
+However, one problem is that the browser uses the sample rate assigned by the system sound device, % is this problem particular to WAV? Seems that way from the text
+and does not have the ability to request a different one. Therefore, the default operation when an audio file is loaded with a different sample rate to that of the system is to convert the sample rate. To provide a check for this, the desired sample rate can be supplied with the setup XML and checked against. If the sample rates do not match, a browser alert window is shown asking for the sample rate to be correctly adjusted. 
+As this happens before any loading or decoding of audio files, the system will only fetch files as soon as the system's sample rate meets any requirements, avoiding requests for large files until they are actually needed. 
 
 During playback, the playback nodes loop indefinitely until playback is stopped. The gain nodes in the \textit{audioObject}s enable dynamic muting of nodes. When a bar in the sliding ranking is clicked, the audio engine mutes all \textit{audioObject}s and un-mutes the clicked one. Therefore, if the audio samples are perfectly aligned up and of the same sample length, they will remain perfectly aligned with each other.
 
 
-\subsection{Setup and Results Formats}\label{sec:setupresultsformats}
+\subsection{Setup and results formats}\label{sec:setupresultsformats}
 
-Setup and the results both use the common XML document format to outline the various parameters. The setup file contains all the information needed to initialise a test session. Several Nodes can be defined to outline the audio samples to use, questions to be asked and any pre- or post-test questions or instructions. Having one document to modify allows for quick manipulation in a 'human readable' form to create new tests, or adjust current ones, without needing to edit which web files.
+[somewhere: check all fragments are played]
 
-The results file is dynamically generated by the interface upon clicking the submit button. There will be checks, depending on the setup file, to ensure that all tracks have been evaluated and their positions in the slider moved. The XML returned contains a node per audioObject and contains its rating in the slider and any comments written in its associated comment box. The rating returned is normalised to be within a integer range of 0 to 100. This normalises the pixel representation of different browser windows. If a window for instance is only 1280 wide, reporting its pixel position is not representative to a display with a width of 1920.
+Setup and the results both use the common XML document format to outline the various parameters. The setup file contains all the information needed to initialise a test session. Several Nodes % capital letter? 
+ can be defined to outline the audio samples to use, questions to be asked and any pre- or post-test questions or instructions. Having one document to modify allows for quick manipulation in a `human readable' form to create new tests, or adjust current ones, without needing to edit which web files. % 'which web files'?
 
-The pre- and post-test options allow for comments or questions to be presented before or after the test. These are automatically generated based upon the given setup XML and allow nearly any form of question and comment to be included in a window on its own. Questions are stored and presented in the response section labelled 'pretest' and 'posttest' along with the question ID and its response. Questions can be made optionally mandatory. Example questions may involve entering mixing experience or listening environment.\\
+The results file is dynamically generated by the interface upon clicking the `Submit' button. This also executes checks, depending on the setup file, to ensure that all tracks have been played back, rated and commented on. The XML output returned contains a node per audioObject and contains both the corresponding marker's position and any comments written in the associated comment box. The rating returned is normalised to be a value between 0 and 100, normalising the pixel representation of different browser windows. 
 
-[LIST OF OPTIONS]\\
+Pre- and post-test dialog boxes allow for comments or questions to be presented before or after the test, to convey listening test instructions, and gather information about the subject, listening environment, and overall experience of the test. These are automatically generated from the setup XML and allow nearly any form of question and comment to be included in a window on its own. Questions are stored and presented in the response section labelled `pretest' and `posttest', along with the question ID and its response, and can be made mandatory. 
+Further options in the setup file are: 
+
+\begin{itemize}
+\item \textbf{Snap to corresponding position}: When this is enabled, and a fragment is playing, the playhead skips to the same position in the next fragment that is clicked. If it is not enabled, every fragment is played from the start. 
+\item \textbf{Loop fragments}: Repeat current fragment when end is reached, until the `Stop audio' or `Submit' button is clicked. 
+\item \textbf{Comments}: Displays a separate comment box for each fragment in the page.
+\item \textbf{General comment}: One comment box, additional to the individual comment boxes, to comment on the test or a feature that some or all of the fragments share. 
+\item \textbf{Resampling}: When this is enabled, tracks are resampled to match the subject's system's sample rate (a default feature of the Web Audio API). When it is not, an error is shown when the system does not match the requested sample rate. 
+\item \textbf{Randomise page order}: Randomises the order in which different `pages' are presented. % are we calling this 'pages'?
+\item \textbf{Randomise fragment order}: Randomises the order and numbering of the markers and comment boxes corresponding with the fragments. This permutation is stored as well, to be able to interpret references to the numbers in the comments (such as `this is much [brighter] then 4'). 
+\item \textbf{Require playback}: Require that each fragment has been played at least once, if not in full. 
+\item \textbf{Require full playback}: If `Require playback' is active, require that each fragment has been played in full. 
+\item \textbf{Require moving}: Require that each marker is moved (dragged) at least once. 
+\item \textbf{Require comments}: This option allows requiring the subject to require a comment for each track. 
+% explanation on how this is implemented? 
+\end{itemize}
+
+When one of these options is not included in the setup file, they assume a default value. 
+
 % loop, snap to corresponding position, comments, 'general' comment, require same sampling rate, different types of randomisation
 
-[LIST OF THINGS THAT ARE LOGGED] (possibly elsewhere)\\
-% time, clicks
+
 
 The results will also contain information collected by any defined pre/post questions. These are referenced against the setup XML by using the same ID as well as printing in the same question, so readable responses can be obtained. Future development will also evolve to include any session data, such as the browser the tool was used in, how long the test took and any other metrics. Currently the results files are downloaded on the user side of the browser as a .xml file to be manually returned. However the end goal is to allow the XML files to be submitted over the web to a receiving server to store them, allowing for automated collection.
 
-Here is an example of the setup XML and the results XML:
+Furthermore, each user action (manipulation of any interface element, such as playback, moving a marker, or typing a comment) is logged along with a the corresponding time code and stored or sent along with the results. % right? 
+
+%Here is an example of the setup XML and the results XML: % perhaps best to refer to each XML after each section (setup <> results)
 % Should we include an Example of the input and output XML structure?? --> Sure. 
 
 ADD XML STRUCTURE EXAMPLE
@@ -236,21 +268,21 @@
 \section{Applications}\label{sec:applications} %?
 discussion of use of this toolbox (possibly based on a quick mock test using my research data, to be repeated with a large number of participants and more data later)\\
 
-\subsection{Listening Environment Standardisation}
+\subsection{Listening environment standardisation}
 
 In order to reduce the impact of having a non-standardised listening environment and unobservable participants, a series of pre-test standard questions have been put together to ask every participant. The first part of this is that every participant is asked to carry out the test, wherever possible, with a pair of quality headphones.
 
 % I think the following should be different for every type of test, so I think it looks better to say any type of question (with text box, or radio buttons, or dropdown menu?) is possible to add. 
-\begin{itemize}
-\item Name (text box)
-%\item I am happy for name to be used in an academic publication (check box) % never really necessary, as far as I'm concerned
-\item First language (text box)
-\item Location: country, city (text box)
-\item Playback system (ratio box: headphone or speaker)
-\item Make and Model of Playback System (text box)
-\item Listening environment (text box)
-%\item Please assess how good you believe your hearing to be, where 1 is deaf, 10 is professional critical listener (Dropdown box 1-10 ) % not sure
-\end{itemize}
+%\begin{itemize}
+%\item Name (text box)
+%%\item I am happy for name to be used in an academic publication (check box) % never really necessary, as far as I'm concerned
+%\item First language (text box)
+%\item Location: country, city (text box)
+%\item Playback system (ratio box: headphone or speaker)
+%\item Make and Model of Playback System (text box)
+%\item Listening environment (text box)
+%%\item Please assess how good you believe your hearing to be, where 1 is deaf, 10 is professional critical listener (Dropdown box 1-10 ) % not sure
+%\end{itemize}
 
 
 There are also a series of considerations that have been made towards ensuring there is a standardised listening environment, so it is possible to
@@ -267,6 +299,7 @@
 \end{itemize}
 
 
+
 [Regarding randomisation: keep the randomisation 'vector' so you can keep track of what subjects are referring to in comment fields]