Simon's Work Blog

ISMIR code release, CAA prep, account problems

2007-06-05T00:24:00.000-07:00

- getaudio-2.1.0, a cleaned up and fully documented version of the software used to extract the stereo sine waves for the ISMIR paper is finished and ready for submission

- prepping 250 word CAA abstract for June 8 with Beinan, awaiting metadata for stereo OPDs. Data is oriented in a new way and will require different method of traversing OPDs than in getaudio-2.1.0, so this will start a different branch (version 3)

- account has been deleted on coltrane and cannot find the Wiki page, so unable to publish software or do scp of *.opd files directly from coltrane. Also having problems with Borges! What in the world is going on in accounts administration over there???

preliminary analysis of achievable SNR

2007-05-01T14:26:00.000-07:00

Problem:
Initial work indicates that using 10X magnification, we are able to achieve sampling frequencies of several hundred kHz and upwards. However, lateral resolution appears to be quite low and the question has been raised if whether the high sampling rate overcomes this quantization error in a manner similar to delta-sigma modulation.

Analysis:
Differential pulse code modulation and delta-sigma modulation operate using the following principles:
1) transmitter/ADC: Using a prediction method, the quantized value of the current input is estimated based on past values. The difference ("delta") between the predicted quantized value and the actual analog value is quantized and stored/transferred digitally.
2) receiver/DAC: Using an identical prediction method to the transmitter/ADC, the quantized value of the current output is estimated based on past output values. By adding these values ("sigma") to the difference values determined in (1), a quantized version of the original output signal is obtained.
3) Quantization noise is further reduced by noise shaping.

It is clear that DPCM or delta-sigma modulation work by attempting to transmit/store the derivative of the analog signal. Since OAR cannot make comparisons with the actual analog position of the groove with the quantized groove, (1) does not occur and the principles do not apply.

However, oversampling alone provides the benefit of lowering the average noise floor in the spectrum. The SNR is identical to a non-oversampled signal, but since the bandwidth is wider, the noise energy is spread out over a larger range. Therefore, LPFing the recovered signal to remove quantization noise outside of the bandwidth of interest increases SNR. With appropriate filtering, each time the sampling rate is doubled we will reduce the noise in the band of interest by 3dB, i.e. gain 0.5 bit of resolution in the band of interest.

There is a good online reference here:
http://www.maxim-ic.com/appnotes.cfm?appnote_number=1870&CMP=WP-10

workflow out for comments, Langlois report completed

2007-03-03T13:13:00.000-08:00

1) mitac_workflow-1.0.0 completed in Visio and sent out for comments

2) Langlois report completed

3) 3D groove tracing algorithm undergoing testing

workflow, Langlois report outline, VAS problem

2007-02-27T19:21:00.000-08:00

1) Discussed workflow outline with Beinan and completed a draft and sent to Beinan for comments. Specifies expected metadata at the handoff of the OPD files, and the re-iterative communication between us. See below:

Expected with each OPD file:
i) vas_offset (see Glossary)
ii) vas_size (see Glossary)
iii) an indication of which groove I will extract data from. This
can be an image file of the VAS display that has been edited in Paint
with a mark on the groove of interest.

Simon's workflow:

a) Beinan does not logout of Vision, move the record or turn off the
computer until Simon has completed (4). After step (3), the data will
not be easily reproduced since the (0,0) stage position drifts upon
each initialization.

b) Retrieve OPD files, and metadata (i), (ii), (iii) from the
temporary data storage folder on the Wiki. http://132.206.14.10/mitac/data/mitac_data_table.htm

Time: 1 h

c) Check that the indicated groove in (iii) for each database lines
up accordingly when loading the images in a large array, each offset
by (i). If the passed off data is correct, we will see the grooves
indicated in (iii) touch each other perfectly between VAS's. If
problem is perceived, inform Beinan on which VAS's to re-measure.

Time: 1-2 h

d) Check quality of grooves within each VAS. If confident that
software will be able to handle it, inform Beinan to turn off machine.
After this point, new data cannot be easily re-measured.

Time: 2-3 h

e) Manually change variables in scripts to account for database
specific details: vas_offset, vas_size, and the specifications of the
initial subarray that will be analyzed by the block-processor. The
initial subarray begins on the groove described in (iii) and traverses
counter-clockwise. Save raw radial distances.

Time: >4 h, depending on amount of data and any troublesome erroneous
datasets that may disturb the groove tracing algorithm

f) Convert raw radial distances to audio and create presentables
(i.e. graphs, etc.) for discussion and analysis.

Time: 1 h

2) Rough Langlois report outline of accomplishments and future plans. Please provide feedback Ich/Beinan
Accomplishments:
- early testing and familiarization with Wyko NT8000 (bug reports, exploring capabilities and issues with sidewalls, data format export)
- resesarch into previous work and vinyl anomalies (Wiki page on Distortion and imperfections in stylus-based vinyl playback, take concepts from Haber and Fribourg to implement MATLAB software)
- software development, maintenance, and bug fixes (ASCII parser, groove tracing algorithm, radial distance extraction algorithm, block processing algorithm), works by differentiating the lateral undulations of a groove bottom
- audio extraction (<1s) from 78rpm laterally-cut Count Basie "The King" and monophonic sine tone from McGill Audio Test Record
- various anomalies observed and adjusted for during this process (erroneous data in grooves, missing bottom groove information, rising/falling trends, etc.)

Future Plans:
- publish findings to a MIR conference
- move software to version 2, completely 3D with scaleable robustness (tradeoff with speed) to deal with non-idealities in the data when tracing a groove or extracing radial distance
- software will extract 1D slices of height information across the groove at each sampling increment and project it onto a line and display the undulating groove as a 3D mesh
- should be able to extract data from laterally-cut and vertically-cut records as well
- should be compatible with workflow proposed above

3) Worked with Beinan today to explore a VAS stitching problem. We are not sure of the origin, but it may be due to a modification of the ConfigEditor.exe settings. There are several .cfg files - we are not sure which one loads the default factory settings.

4) getaudio-1.0.7 description on Wiki completed.
http://coltrane.music.mcgill.ca:16080/DDMAL/index.php/Audio_Extraction_Software_%28getaudio-1.0.7%29

5) Continuing coding work as discussed earlier

Haber document re-read, Wiki update, S/W update

2007-02-23T08:39:00.000-08:00

1) Review all Haber documents new and old for method of obtaining radius. My comments on Haber's process for 78rpm lateral groove outlined below:

a) Illuminate and capture image such that groove bottom is sharply contrasted with sidewalls. Captured images show clear bright streaks and sharply contrasting sidewalls as dark streaks.

b) Program determines disk center and follows groove trajectory spiralling inwards in cylindrical coordinates (R, Φ)

c) Every 8 microns along groove, measure R of groove bottom by determing where the bright groove bottom streak transitions to the sidewalls. This leads to 2 R measurements every 8 microns (61.3 kHz @ 60mm radius), corresponding to the inner and outer light/dark transition of the groove bottom. Strong dependence on edge quality i.e. sharpness of contrast between groove bottom and sidewalls.

d) Take average of the 2 R measurements at every 8 microns

e) Find Ro, C, A, and Φo such that R’-R is minimized for the whole dataset where R’ = Ro + C*Φ’ + A*(sin(Φ’ + Φo))^2.
i. Ro fit eliminates DC bias
ii. C*Φ’ fit eliminates linear progressive bias. This results from constant steady pressure against the stylus as the groove pushes inward, thus there is no current-generating velocity of the stylus magnet in the inducting coil of the cartridge.
iii. A*(sin(Φ’ + Φo))^2 fit eliminates oscillating “wow” effect. This would be a low frequency modulation effect, with a frequency in the same magnitude as the disk revolution frequency. I missed this before - this acknowledges the existence of the sinusoid-ish rising/falling trends in the data we observed.

f) Once R’ is found to optimally fit R, R’-R is taken as the true undulation of the stylus magnet.

2) Working on Wiki update to fully document the software that was used for the extraction of the sine test tone in November. Will document each module separately.

3) Software update to version 2.0.0 moving along. Plan is to work in 3D, with more intelligent groove tracing algorithm. More details to follow.

MItAC update

2006-11-15T00:15:00.000-08:00

- first audio extraction complete from 78rpm, see getaudio-1.0.6
- first extractions from 33rpm test record complete (1khz, 10khz)

TO DO:
- OPD parser data has incorrect orientation, waiting on fix to begin improving algorithm for audio extraction, since it virtually eliminates wait time on parsing
- investigate ways to include depth in audio extraction
- investigate non-unity pixel aspect ratio role in low frequency modulation observed in getaudio-1.0.6 results

MItAC update

2006-10-19T17:02:00.000-07:00

- October 2006 progress update. Includes links to beta code for audio extraction
http://coltrane.music.mcgill.ca:16080/DDMAL/index.php/October_2006

- previous bug with parsing databases in flipped fashion fixed, updated Randparser on Wikipedia to 1.2.0

- Beinan is writing a program to replace "Bad" occurrences in ASCII datasets with 0 for the purposes of speeding up the textscan() parsing function in MATLAB

- extracted two grooves out of 01.asc. Testing and extraction work ongoing

TO DO:
- extract audio from all databases, stitch them together

MItAC update

2006-10-16T20:59:00.000-07:00

- integrated groove tracing algorithm, radial differentiation algorithm, and random access parser. Some problems were found with the parser, and these corrections have been added to create version 1.1.0 of Randparser

- unlike Fribourg and LBNL, the data is presented to the CPU projected on its natural spiral axis without having been unwrapped. My method requires user to specify initial subarray within database containing first part of groove and also its direction. Radians per sample is fixed to the sampling rate and at each increment, we measure distance from intersection between groove and radial line to the center. As the angle falls out of the subarray, the groove tracer and random access parser extract the next subarray. Once these distances are found, we can remove the DC, remove the DC ramp (spiral), normalize, and differentiate.

- appears to work with limited tests on 01.asc. Difficulty is time consumption, the bottleneck is textscan(), a MATLAB function used to load text from an ASCII file. With homogeneous data it is faster, but since we use it with inhomogeneous data (floating points are intermixed with "Bad" data), it's slow. Most of the time is spent parsing subarrays as we move within database. Maybe we can just patch in a C++ parser in the future

- some final things with the parser need to be checked. I parsed subsections of 01.asc and it appears to be horizontally inversed from 01.jpg. Damon is going to see if he gets the same results with the original MITAC parser

- rough estimate is 10 hours to extract audio from 01.asc from top to bottom at 44.1kHz. Reducing sampling rate does not improve performance since bottleneck is the textscan() function in the parser. This is making testing very difficult and time consuming. Once I can confirm it is working with 01.asc, we can run several computers overnight and check the sound in a matter of days

TO DO:
- find out why databases appear reflected in Randparser. Is this in MITAC parser too? Manual inspection of database seems to indicate that Randparser is working correctly as I understood the database. This means I didn't understand the database - maybe it is flipped horizontally

- pick the exact groove in all databases, then distribute CPU load to others with MATLAB. Expected total CPU time is 320 hours for all 32 databases

- record this groove from a turntable so we have the audio we are aiming for

MItAC update

2006-10-05T20:37:00.000-07:00

- completed scripts that can traverse images of spirals and extract radial distance with respect to center. This is done in a block processing manner, where only subarrays of portions of the groove are extracted to work with. The angular spacing between radial distance measurements is controlled by a chosen sampling rate.

- currently I am integrating the MATLAB scripts for: random parsing, groove tracing, and radial differentiation so that I can start loading the databases and extracting audio

TO DO:
- Beinan has provided 32 databases. Need to reclarify the provided data before he leaves for ISMIR

MItAC update

2006-09-25T21:50:00.001-07:00

- Wiki documentation for random access parser completed (http://coltrane.music.mcgill.ca:16080/DDMAL/index.php/Block_processing_parser)

- fixed small typo bugs in random access parser 1.0.0, updated to 1.0.1

- completed groove tracing algorithm i.e. it can decide what block the random access parser should retrieve next to maintain continuity of the groove based on the trajectory of the current groove section observed

- started development of radial differentiation, but need to verify global position data from the header first

TO DO:
- investigate global positioning accuracies in the provided headers: recall there is an offset between the global center according to Vision and the center of the physical vinyl

- post groove tracing code on Wiki and document

- once global positioning data is verified, need to complete radial differentiation

MItAC update

2006-09-25T21:50:00.000-07:00

MItAC update

2006-09-07T23:24:00.000-07:00

- account on CLUMEQ (linux cluster) granted. It has capability to assign arbitrary amounts of RAM to processes. No distributed toolbox for MATLAB. Preliminary tests parsing databases does not show increased speed compared to our workstations when running on single node of the cluster. CLUMEQ admin says distributed toolbox may be in the works. CLUMEQ has capability for distributed C++, etc.

- parser optimized for speed and memory efficiency completed and verified, posted on Wiki. It allows random access into ASCII database for subimages with integer downsampling.

- switching to part-time 10 hours a week for the duration of the Fall

- vacation to Tokyo/Manila booked: Jan.7-Feb.11 (possibility to do light work remotely)

TO DO:
- complete Wiki documentation on minimal parser
- work on intelligent groove tracing with new random access parser

MItAC update

2006-08-30T13:34:00.000-07:00

- 24 hours into parsing 1GB dataset, hit 'OUT OF MEMORY' error on CAML-5:
??? Error using ==> vertcat
Out of memory. Type HELP MEMORY for your options.

- since we do not yet have access to Veeco software calls, we cannot selectively scan so we will start selectively parsing

- documented new bug in Veeco Vision bug blog, bug with Stage File Stitching

- looking into getting an account on CLUMEQ supercomputer http://www.clumeq.mcgill.ca/ and possibilities of speed improvements with our datasets (ie. do we need to parallelize our code?)

MItAC update

2006-08-29T13:37:00.000-07:00

- finally managed to verify parser for all test datasets generated from Vision 3.60
- what was thought as unproportional completion times for parser (10MB - 1 minute, 60MB - 1:45min) is actually due to fragmentation of bad data within the Z profile data amongst the good data
- will attempt to parse http://132.206.14.10:16080/mitac/data/78-5-85-3-0-1-5_100ms_raw-float_comp-xyz-pixel_new.asc
without block processing on CAML-5 to see if memory constraints will become an issue. Note that this database is approximately 1GB and CAML-5 has 2GB physical RAM, this may require lockdown of CAML-5 for over 24 hours

MItAC update

2006-08-21T20:39:00.000-07:00

- two-point differentiation on old "500ms" images completed (actually only 5ms)
- solved power-on issue (white reset button left of computer should be illuminated to enable power-on)
- installed v3.60, investigated stitching issues (there seems to be size limitations with circular, also we have yet to achieve a "donut")

TO DO:
- investigate stitching and relations to size, time, memory consumption, overlap, etc.

MItAC update

2006-08-17T20:12:00.000-07:00

- extracted audio from OLD 500ms databases (this is apparently in reality close to 100ms due to math error)
- extraction without spiral unwrap possible due to negligible curvature of images
- correct playback rate to be determined since area of these images is not known yet

TO DO:
- two point differentiation to model stylus velocity
- solve power issue with microscope
- figure out how to unwrap partial spiral

MItAC update

2006-08-15T20:51:00.000-07:00

- documenting all possible turntable imperfections/distortions, posting on Wiki
- summarizing reports on all past work in image/audio conversion (LBNL, Fribourg), posting on Wiki
- July 2006 Wiki update
- received software update, forward Coakley's contact to Ich

TO DO:
- parser is complete, need to finish spiral on partial picture ASAP (absolute position help?), Ich says trace by hand could be acceptable for now
- look into differentiation of path once spiral unwrap complete
- double check Damon's math for 100ms, 500ms measurements on inner groove
- upload code and images to Wiki

MItAC update

2006-08-10T08:16:00.000-07:00

- algorithm to locate approximate center of spiral (when entire spiral contained in image) is complete
- due to stitching and memory limitations, currently developing algorithm to locate center of spiral with only incomplete image of spiral
- current approaches will require absolute position data from Vision output header
- we will attempt to extract approx 100ms of sound from innermost grooves due to requirement for less images in comparison with outer grooves

MItAC update

2006-08-04T13:52:00.000-07:00

1) created fake spiral data, beginning work on center locating algorithm

2) top-level design appears to match Haber's previous work in 78rpm audio recovery

3) investigation into memory requirements
- please watch http://www.mathworks.com/cmspro/req11290.html?eventid=32518 which describes how to handle large datasets in MATLAB
- 32-bit machine - max 2-3GB, MacOS - max 3-4GB, 64-bit Linux - max 16 GB
- need to consider block processing and image downsampling (textscan, memmapfile)
- data storage - convert from double in Vision to integers
- process - trade speed for memory by devectorizing operations, nesting, using pointers rather than copy write operations between functions, useful tool "monitormatlab"
- plotting - need to downsample

MItAC update

2006-08-03T15:38:00.000-07:00

1) new readings and additions to Wiki bibliography ("The Columbia Long-Playing Microgroove Recording System" and "Recording and Reproducing Standards")

2) software top-level design (assuming parser hands over 2D array of Z heights)
a) getbottom.m - normalizes heights and removes data above threshold to leave bottom groove only
b) findcenter.m - locates center of record (whether in array or outside of array) by finding peak correlation with circles of various sizes
c) findgrooves.m - locate grooves along left or bottom axis (start) and indexes their start locations.
d) findspacing.m - determines spacing of grooves from groove locations
e) unwrap.m - unwraps undulations onto the 1D axis

MItAC update

2006-08-02T12:21:00.000-07:00

- initial software development plan
1) Parser (Damon)
- goal is to translate ASC dataset into 2D array in MATLAB
2) Setup for audio recovery (Simon)
- goal is to do initial study on technique described below
a) filter top of groove, use only bottom groove and create line of best fit
b) extract single groove from large rectangular stitched image (2D array)
c) fit circular curvature to the groove, extract difference and unwrap groove
d) play sound from displacement from fitted circular curvature

- reported new bugs to Jeff Pageau / Tom Coakley (see http://visionbugs.blogspot.com/)
- software should be shipping out tomorrow from Tucson, wait for a week to speak with Tom about install or call field engineers in Tucson

MItAC update

2006-08-01T20:41:00.000-07:00

- preliminary layout and annotated bibliography on Wiki, needs further work on format and will be updated as more papers are read
- further reading into tonearm physics and groove dimensional standards for 78, 33, and 45 rpm
- although summaries and references have been found relating to Columbia intial standard and RIAA standard, will ask for assistance tomorrow to find P. C. Goldmark, R. Snepvangers, and W. S. Backman. "The Columbia Long-Playing Microgroove
Systems," Recording System," Proc. IRE, vol. 37, pp. 923-927
- starting to plan software development for obtaining sound from 78rpm image, reading on vinyl physics ramping down

MItAC update

2006-07-31T10:14:00.000-07:00

- rough notes on vinyl physics available here:
http://www.music.mcgill.ca/~deleon/phonograph_notes.doc
- above document will be updated regularly as readings continue
- main ideas from AES articles highlight imperfections of vinyl playback that inevitably lead to upper harmonic distortions, perhaps these can be avoided optically and then physically modeled back into the clean audio for a comparison study of preference

MItAC update

2006-07-26T21:25:00.000-07:00

- reading and note-taking continuing on vinyl physics, a few interesting facts that may have direct consequence to our study

cutters use carriage that moves radially across vinyl, whereas playback turntables typically rotate from a pivot. Thus such turntables suffer from unavoidable pitch/azimuth errors
RIAA reproduction EQ curve (the inverse of the RIAA lathe cutter curve) does not account for the typical 50kHz rolloff in most lathes. Optical methods could allow properly compensating reproduction curve, as well as compensate for non-standard EQ curves used prior to standardization
curvature of playback stylus greatly determines amplitude of certain frequencies i.e. elliptical stylus fits into tightly packed modulations better and allows for more displacement, thus explaining better response to higher frequency. Optical method completely avoids this and is now only limited by groove space requirements and capabilities of cutter
tracing distortion (caused by differences in linear travel speed of stylus across record width) is unavoidable, and results in different frequency performance in inner and outer grooves. Outer modulations perform better at higher frequencies since modulations are stretched out, which is the same principle as improving sound quality via increasing rpm. Again optical method completely avoids this in theory

- updated Wiki to include vinyl physics links found on the internet. Draft status
- EndNote database started to incorporate large body of work in Journal of AES on phonographs

MItAC update

2006-07-25T07:33:00.000-07:00

- new software arriving to resolve Vision stitching problems
- all future bugs and software issues will be posted at http://visionbugs.blogspot.com/ in addition to our personal blogs for organization and to avoid redundancy
- wealth of phonograph studies on JAES, currently reading and note taking
- current plan is to have a one-on-one tutorial Friday afternoon to teach each other what we have learned thus far (Damon=interferometry, Simon=vinyl physics)
- microscope software familiarity work will halt until new software arrives

Vision stitching bugs

2006-07-20T23:35:00.000-07:00

1) Circular/Annular stitching does not support stitch from current location. Specifying an inner / outer diameter with "Use Current Location" starting option selected will still result in a modal dialogue that disables other actions when taking a new measurement. The modal dialogue requests for the user to specify boundaries for circular stitching, which can only be completed in the stitching "Teach" procedure.

2) Crashing Vision in Circular/Annular stitching mode
a) We specify inner/outer dimensions manually with Turret = 5x , FOV = 1x

Outer left edge of the sample: in our test, left corner of the "Y"
Outer top edge: two grids up and right from the origin
Outer bottom edge: 4 grids down from upper top edge point
Inner bottom edge: 1 grid up from bottom edge point
Resulting diameters

Outer: 0.4765 mm
Inner: 0.2315 mm

b) Select "New Measurement" results in a modal dialogue requesting the manual specification of outer left edge followed by clicking "Next". The "Next" button is greyed out and only clicking "Finish" will start stitching.

c) During measurement, the microscope appears to attempt to scan at a larger area than specified. It starts correctly at the outer left edge, but the other locations chosen seem to be offset from the other locations specified (outer top edge, outer bottom edge, inner bottom edge). From our limited observations, the three boundaries seem to be moved up and to the right from their originally specified locations.

d) After taking measurements and camera returns to outer left edge, Vision crashes with no prompt or error message.

3) Freezing and crashing Vision when attempting to use Stage File stitching using a manually created stage file from X/Y Grid. See Damon's blog (http://damonli.blogspot.com/) for complete description. Will contact Veeco sales tomorrow with regards to bugs encountered for software update. We are currently using 3.50, released 8/8/05.

4) Familiarization with Wiki syntax and summaries of VisualAudio and LBNL. Hierarchical structure of http://coltrane.music.mcgill.ca:16080/DDMAL/index.php/Preservation to be decided with Damon tomorrow.

MItAC update (July 19, 2006)

2006-07-20T10:31:00.000-07:00

- obtained reading material for phonograph/gramophone characteristics
- rectangular stitching familiarization: specify length/width, and current FOV will be lower left
- circular stitching familiarization: specify inner/outer diameter (circular or annulus), optionally can select "learn" to manually pinpoint outer left edge/top edge/bot edge, etc., where it seems we were sometimes able to crash Vision, and once crash Windows in this manual mode (suspected it may be due to improper manual specification of annulus)

- blue screen: "The problem seems to be caused by the following file: bcam.sys"

- PAGE_FAULT_IN_NONPAGED_AREA
- Technical Information: STOP: 0x00000050 (0xE0617000, 0x00000001, 0xF77192DD, 0x00000000)
- bcam.sys

- Address F77192DD
- Base at F7712000
- Date stamp 416ffae0

- stage file stitching familiarization: not yet started
- ignoring bug, it appears that annulus stitch could be used to scan an entire record, so long as backscan and length are sufficient to account for surface height changes

interesting links for vinyl physics

2006-07-18T12:19:00.000-07:00

- http://www.vinylrecorder.com/stereo.html illustrates stereo groove modulation. While vertical and lateral modulation were both used for 78rpm mono, lateral modulation became the standard because of groove durability and the fact that large amplitudes of vertical modulation would virtually eliminate the groove. Instead of implementing stereo with vertical/lateral, problem of vertical avoided by compromising both sidewalls to modulate at 45deg, phase-shifted 180.
- http://en.wikipedia.org/wiki/Gramophone_record wikipedia article, great overall picture from history to materials and manufacturing
- http://www.aardvarkmastering.com/riaa.htm RIAA dimensions and standards
- http://www.euronet.nl/~mgw/background/riaa/uk_riaa_background_1.html RIAA equalization graphs
- http://eil.com/explore/guide/vinyl_making.asp great background info on cutting vinyl master discs to manufacturing stampers
- http://www.vestax.com/v/products/recorders/vrx2000.html (Vinyl lathe, ~$10,000 USD), http://www.vinylrecorder.com/order.html (Vinyl lathe, ~$4000 euro)
- http://www.music.mcgill.ca/~deleon/courses_files/mumt611_files/mumt611_a6_deleons.pdf my presentation on image to audio conversion for MUMT611, an overview of its current state as of April 2006
- http://www-cdf.lbl.gov/%7Eav/ LBNL sound reproduction page containing movies, audio, and papers of Fadeyev and Haber's work for wax cylinders

MitAC update

2006-07-17T21:59:00.000-07:00

- Naming convention for images agreed upon 33/45/78-backscan-length-modthresh-datarestorepixels-fov-turret-Z
- Choice of known experimental 78rpm for intial studies - "There's a tear in my beer tonight" by Hoosier Hot Shots and Sally Foster, Damon is searching for clean digital copy and we plan to record it from a turntable
- Platter, record mat and approximate thread match found, longer screws and washplates to be purchased Tuesday from Home Depot to complete microscope stage assembly
- Partial delegation of short-term research responsibilites: Damon (physics of white light interferometry, stitching methods), Simon (physics of vinyl manufacturing/cartridges/lathes, Wikipedia literature update for LBNL etc., complete platter stage assembly), both (familiarization with imaging capabilities to the level of Tom's images and to begin stitching feasibility study)
- Currently capable of achieving images as described by Veeco salesman in tutorial (clear top/bottom groove, no sidewalls), this is partially circumvented by enabling data restore (linear interpolation) but is not of the quality of Tom's VSI images in Ich's powerpoint slides
- the problem appears to be focusing in deep cracks (~30um) rather than post processing since fringe patterns do not appear on sidewalls regardless of tilt, filter, fov, turret, intensity, and fringes appear successfully on top groove and bottom during scan
- ASCII datasets seem to be the choice output format due to options to incorporate post-processing and better than 8-bit resolution, rather than TIFF as previously suggested