Introducing the River View Web Player & Other News from River Studies
It has been a long while since my last blog entry in regards to river view panoramas. In the meantime the recording setup runs basically stable (putting aside minor problems with loose connectors) even under rough conditions (see also the gallery “Making Of” at the end of this post).
I just came back from artist-in-residency stays in Varanasi/Benares and Guwahati in India, that enabled me to have a few extensive recording sessions on various vessels like house boats, motor and rowing boats on Ganges River – for one the most sacred river to Hindus and probably most worshipped river on the planet, next to being one of the most polluted rivers of the world – and Brahmaputra River in Assam.
Many thanks go to Kriti Gallery in Varanasi and the Periferry project in Guwahati for hosting me and helping me to get onboard.
Web PlayerMeanwhile I also just finished the “River View Web Player” as a public online Beta Version. It runs on openlayers and geodjango and features the growing archive and collection of river views (up to now including views of Ganges, Brahmaputra, Danube and Nile River). There are still plenty of things to polish up, some image material to be retouched and/or uploaded, but see yourself here:
River View Web Player
Using ElphelI am using an Elphel 353 equipped with 8 or 16mm movie lenses from the seventies to acquire this imagery. The camera delivers a Window-of-Interest video stream of 2592 x 48 pixel size with a variable frame rate between 1 and 300fps (changed on the fly according to the speed of the vessel and distance to the object of focus. That is done manually and under visual control: similar to the auto-focus mechanism, it is also a question of choice and decision and therefore not easily automatable).
The video stream is then processed and saved by custom software.
I am not using Elphel’s internal linescan/photofinish for now, since it still behaves pretty unstable and unpredictable when changing parameters like TRIGGER, VIRT_KEEP and VIRT_HEIGHT on the fly. Also, having a line per frame allows me for a more fine-graded control and preview as long as enough frames are delivered.
Elphel’s internal linescan mode, however, works quite well and stable if it runs as fast as it goes or once you have fixed a setup – as some testing on Austrian Highways prove (find more here):
Elphel 353 in Linescan mode on Austrian Highway A1 - approx. 120km/h, 2000 lps
SourcesThe source code of both, my recording software malisca and the web app and player, are open on my github repository.
Making Of / GalleryA brief guided tour to Ganges and Brahmaputra river recordings in pictures:
On Ganges
Elphel on Ganges River
river recording setup: Thinkpad, Elphel 353, battery pack and USB-GPS-receiver
another shot of recording setup (including an improvised tent)
.. staring into the lens ..
.. obstacles (pontoon bridge) ..
lunch break on Ganges River
Elphel on Brahmaputra River
Not yet, but I would love this setup to be powered by solar energy ....
[elphel353-8.0] By elphel: Increased drive to 4mA (from 2 mA), now the eye is nearly 180 degrees with 450mm cable
Increased drive to 4mA (from 2 mA), now the eye is nearly 180 degrees with 450mm cable
- Modified x359.bit rev1.33 - added 28 lines, removed 28 lines
- Modified x359.ucf rev1.13 - added 20 lines, removed 20 lines
[elphel353-8.0] By elphel: 8.2.0
8.2.0
- Modified target.list rev1.85 - added one line, removed one line
[elphel353-8.0] By elphel: 8.2.0
8.2.0
- Modified elphel_release rev1.83 - added one line, removed one line
[elphel353-8.0] By elphel: added packages/initscripts/respawnd-R1_0_2/Makefile
added packages/initscripts/respawnd-R1_0_2/Makefile
- Modified src.list rev1.96 - added 4 lines, removed none
[elphel353-8.0] By elphel: enabled respawnd in level4 (for telnetd)
enabled respawnd in level4 (for telnetd)
- Modified Makefile rev1.1 - added none, removed none
[elphel353-8.0] By elphel: Release 8.1.2.6
Release 8.1.2.6
- Modified target.list rev1.84 - added 7 lines, removed 6 lines
[elphel353-8.0] By elphel: release 8.1.2.6
release 8.1.2.6
- Modified src.list rev1.95 - added 9 lines, removed one line
[elphel353-8.0] By elphel: 8.1.2.6
8.1.2.6
- Modified elphel_release rev1.82 - added one line, removed one line
[elphel353-8.0] By elphel: some cleanup
some cleanup
- Modified nfs_update rev1.18 - added 26 lines, removed 19 lines
[elphel353-8.0] By elphel: keyword substitution: kv...
keyword substitution: kv total revisions: 11; selected revisions: 11 description:
- Modified Makefile rev1.10 - added none, removed none
[elphel353-8.0] By elphel: changed init sequence
changed init sequence
- Modified fpga rev1.32 - added 7 lines, removed none
[elphel353-8.0] By elphel: Enable telnet in reflash mode (after netboot cmd=boot)
Enable telnet in reflash mode (after netboot cmd=boot)
- Modified Makefile rev1.1 - added none, removed none
[elphel353-8.0] By elphel: unmounting flash in reflash mode (init 4) to prevent dependency on corrupted files
unmounting flash in reflash mode (init 4) to prevent dependency on corrupted files
- Modified Makefile rev1.1 - added none, removed none
- Modified rc_noflash rev1.1 - added none, removed none
[elphel353-8.0] By elphel: enable serial console in reflash mode
enable serial console in reflash mode
- Modified inittab rev1.1 - added none, removed none
[elphel353-8.0] By elphel: Added newer version (1.2.0) that supports updating BBT
Added newer version (1.2.0) that supports updating BBT
- Modified nandwrite.c rev1.1 - added none, removed none
[elphel353-8.0] By dzhimiev: 1. added UI for editing the filelist of upgrade surviving files
1. added UI for editing the filelist of upgrade surviving files
- Modified src.list rev1.94 - added 4 lines, removed none
- Modified target.list rev1.83 - added one line, removed none
- Modified Makefile rev1.11 - added one line, removed one line
- Modified firmware.php rev1.17 - added 105 lines, removed 6 lines
- Modified store.php rev1.1 - added none, removed none
[elphel353-8.0] By elphel: 8.1.2.1
8.1.2.1
- Modified elphel_release rev1.81 - added one line, removed one line
[elphel353-8.0] By elphel: increased initial sensor clock frequency (20MHz->40MHz)
increased initial sensor clock frequency (20MHz->40MHz)
- Modified pgm_functions.c rev1.23 - added 5 lines, removed 2 lines
[elphel353-8.0] By elphel: more debug output (if enabled)
more debug output (if enabled)
- Modified multisensor.c rev1.19 - added 6 lines, removed 2 lines
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