From c10252a9ee43e329fbc9ec5fd345a541cc1f1fb3 Mon Sep 17 00:00:00 2001
From: Matt <sixteenmillimeter@riseup.net>
Date: Sat, 18 Jun 2016 20:49:39 -0400
Subject: [PATCH] capture-report library for creating a telecine method
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The purpose of this module will be to generate a report of the
projector actions that can be translated into rendering instructions
for a telecine.

First tests will be done on a Blackmagic Pocket Cinema camera which
will record a 4000 frame sequence (100ft of 16mm). The report will
allow me to record the entire sequence of the projector advancing 4000
frames and will make a list of acceptable frames to pull out for
stitching together into a sequence. It is amazingly inefficient in
terms of disk space, but will make this setup much cheaper than one
that requires purchasing hardware to capture images to disk during
operation.

Rubber ducking: The report will watch for projector start and end times
in milliseconds, with a “start” value to be factored in later. On every
projector start and end event, when capture is active, an event with
the millisecond of the occurrence is logged to the report. At the end
of the sequence, the report will be parsed to determine the acceptable
frames to export into a new sequence. This will be determined by
finding a period between proj_end and proj_start events and dividing
that into frames and picking the central most frame.

Acceptable frames, marked by frame numbers, get put into an render list
that gets pegged to a first frame and adjusted via offset. The export
list will be fed into a command that will go through either a video
file or an image sequence and output the determined frames into an
image sequence that will be stitched together with ffmpeg/libav.
---
 app/lib/capture-report.js | 108 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 app/lib/capture-report.js

diff --git a/app/lib/capture-report.js b/app/lib/capture-report.js
new file mode 100644
index 0000000..be7042a
--- /dev/null
+++ b/app/lib/capture-report.js
@@ -0,0 +1,108 @@
+var capture = {},
+	fs = require('fs'),
+	exec = require('child_process').exec;
+
+capture.active = false;
+capture.store = {};
+
+capture.start = function () {
+	'use strict';
+	capture.store.events = [];
+	capture.store.start = +new Date();
+};
+
+capture.proj_start = function () {
+	'use strict';
+	var e = {
+		'start' : +new Date()
+	};
+	capture.store.events.push(e);
+};
+
+capture.proj_end = function () {
+	'use strict';
+	var e = {
+		'end' : +new Date()
+	};
+	capture.store.events.push(e);
+};
+
+capture.report = {};
+
+capture.report.parse = function (first, report, fps, type) {
+	'use strict';
+	var output = [],
+		frame,
+		last = null,
+		buffer;
+	if (typeof fps === 'undefined') {
+		fps = 24;
+	}
+	frame = 1000 / fps; 
+	if (typeof report === 'undefined') {
+		report = capture.store;
+	} else {
+		report = JSON.parse(fs.readFileSync(report, 'utf8'));
+	}
+	if (typeof type === 'undefined') {
+		type = 'still';
+	}
+	if (typeof first === 'undefined') {
+		first = 0;
+	}
+	if (type === 'still') {
+		//first clean frame
+		for (i = 0; i < report.events.length; i++) {
+			if (typeof report.events[i].start !=== 'undefined') {
+				buffer = report.events[i].start;
+				if (last !== null) {
+					
+					output.push();
+				}
+			} else {
+				buffer = report.events[i].end - buffer;
+				last = report.events[i].end;
+			}
+		}
+
+	} else if (type === 'video') {
+
+	}
+	return output;
+};
+
+capture.report.render = function () {
+	'use strict';
+
+};
+
+capture.test = function () {
+	'use strict';
+	var i = -1,
+		len = 10,
+		intval,
+		next = function () {
+			i++
+			if (i === len) {
+				clearInterval(intval);
+				intval = null;
+				console.dir(capture.store);
+				parse();
+			} else {
+				if (i % 2 === 0) {
+					capture.proj_start();
+				} else {
+					capture.proj_end();
+				}
+			}
+	},
+	parse = function () {
+		capture.report.parse();
+	};
+	capture.start();
+	intval = setInterval(next, 800);
+};
+
+
+capture.test();
+//module.exports = capture;
\ No newline at end of file