/*jshint node:true*/
'use strict';
var fs = require('fs');
var path = require('path');
var PassThrough = require('stream').PassThrough;
var async = require('async');
var utils = require('./utils');
/*
* Useful recipes for commands
*/
module.exports = function recipes(proto) {
/**
* Execute ffmpeg command and save output to a file
*
* @method FfmpegCommand#save
* @category Processing
* @aliases saveToFile
*
* @param {String} output file path
* @return FfmpegCommand
*/
proto.saveToFile =
proto.save = function(output) {
this.output(output).run();
return this;
};
/**
* Execute ffmpeg command and save output to a stream
*
* If 'stream' is not specified, a PassThrough stream is created and returned.
* 'options' will be used when piping ffmpeg output to the output stream
* (@see http://nodejs.org/api/stream.html#stream_readable_pipe_destination_options)
*
* @method FfmpegCommand#pipe
* @category Processing
* @aliases stream,writeToStream
*
* @param {stream.Writable} [stream] output stream
* @param {Object} [options={}] pipe options
* @return Output stream
*/
proto.writeToStream =
proto.pipe =
proto.stream = function(stream, options) {
if (stream && !('writable' in stream)) {
options = stream;
stream = undefined;
}
if (!stream) {
if (process.version.match(/v0\.8\./)) {
throw new Error('PassThrough stream is not supported on node v0.8');
}
stream = new PassThrough();
}
this.output(stream, options).run();
return stream;
};
/**
* Generate images from a video
*
* Note: this method makes the command emit a 'filenames' event with an array of
* the generated image filenames.
*
* @method FfmpegCommand#screenshots
* @category Processing
* @aliases takeScreenshots,thumbnail,thumbnails,screenshot
*
* @param {Number|Object} [config=1] screenshot count or configuration object with
* the following keys:
* @param {Number} [config.count] number of screenshots to take; using this option
* takes screenshots at regular intervals (eg. count=4 would take screens at 20%, 40%,
* 60% and 80% of the video length).
* @param {String} [config.folder='.'] output folder
* @param {String} [config.filename='tn.png'] output filename pattern, may contain the following
* tokens:
* - '%s': offset in seconds
* - '%w': screenshot width
* - '%h': screenshot height
* - '%r': screenshot resolution (same as '%wx%h')
* - '%f': input filename
* - '%b': input basename (filename w/o extension)
* - '%i': index of screenshot in timemark array (can be zero-padded by using it like `%000i`)
* @param {Number[]|String[]} [config.timemarks] array of timemarks to take screenshots
* at; each timemark may be a number of seconds, a '[[hh:]mm:]ss[.xxx]' string or a
* 'XX%' string. Overrides 'count' if present.
* @param {Number[]|String[]} [config.timestamps] alias for 'timemarks'
* @param {Boolean} [config.fastSeek] use fast seek (less accurate)
* @param {String} [config.size] screenshot size, with the same syntax as {@link FfmpegCommand#size}
* @param {String} [folder] output folder (legacy alias for 'config.folder')
* @return FfmpegCommand
*/
proto.takeScreenshots =
proto.thumbnail =
proto.thumbnails =
proto.screenshot =
proto.screenshots = function(config, folder) {
var self = this;
var source = this._currentInput.source;
config = config || { count: 1 };
// Accept a number of screenshots instead of a config object
if (typeof config === 'number') {
config = {
count: config
};
}
// Accept a second 'folder' parameter instead of config.folder
if (!('folder' in config)) {
config.folder = folder || '.';
}
// Accept 'timestamps' instead of 'timemarks'
if ('timestamps' in config) {
config.timemarks = config.timestamps;
}
// Compute timemarks from count if not present
if (!('timemarks' in config)) {
if (!config.count) {
throw new Error('Cannot take screenshots: neither a count nor a timemark list are specified');
}
var interval = 100 / (1 + config.count);
config.timemarks = [];
for (var i = 0; i < config.count; i++) {
config.timemarks.push((interval * (i + 1)) + '%');
}
}
// Parse size option
if ('size' in config) {
var fixedSize = config.size.match(/^(\d+)x(\d+)$/);
var fixedWidth = config.size.match(/^(\d+)x\?$/);
var fixedHeight = config.size.match(/^\?x(\d+)$/);
var percentSize = config.size.match(/^(\d+)%$/);
if (!fixedSize && !fixedWidth && !fixedHeight && !percentSize) {
throw new Error('Invalid size parameter: ' + config.size);
}
}
// Metadata helper
var metadata;
function getMetadata(cb) {
if (metadata) {
cb(null, metadata);
} else {
self.ffprobe(function(err, meta) {
metadata = meta;
cb(err, meta);
});
}
}
async.waterfall([
// Compute percent timemarks if any
function computeTimemarks(next) {
if (config.timemarks.some(function(t) { return ('' + t).match(/^[\d.]+%$/); })) {
if (typeof source !== 'string') {
return next(new Error('Cannot compute screenshot timemarks with an input stream, please specify fixed timemarks'));
}
getMetadata(function(err, meta) {
if (err) {
next(err);
} else {
// Select video stream with the highest resolution
var vstream = meta.streams.reduce(function(biggest, stream) {
if (stream.codec_type === 'video' && stream.width * stream.height > biggest.width * biggest.height) {
return stream;
} else {
return biggest;
}
}, { width: 0, height: 0 });
if (vstream.width === 0) {
return next(new Error('No video stream in input, cannot take screenshots'));
}
var duration = Number(vstream.duration);
if (isNaN(duration)) {
duration = Number(meta.format.duration);
}
if (isNaN(duration)) {
return next(new Error('Could not get input duration, please specify fixed timemarks'));
}
config.timemarks = config.timemarks.map(function(mark) {
if (('' + mark).match(/^([\d.]+)%$/)) {
return duration * parseFloat(mark) / 100;
} else {
return mark;
}
});
next();
}
});
} else {
next();
}
},
// Turn all timemarks into numbers and sort them
function normalizeTimemarks(next) {
config.timemarks = config.timemarks.map(function(mark) {
return utils.timemarkToSeconds(mark);
}).sort(function(a, b) { return a - b; });
next();
},
// Add '_%i' to pattern when requesting multiple screenshots and no variable token is present
function fixPattern(next) {
var pattern = config.filename || 'tn.png';
if (pattern.indexOf('.') === -1) {
pattern += '.png';
}
if (config.timemarks.length > 1 && !pattern.match(/%(s|0*i)/)) {
var ext = path.extname(pattern);
pattern = path.join(path.dirname(pattern), path.basename(pattern, ext) + '_%i' + ext);
}
next(null, pattern);
},
// Replace filename tokens (%f, %b) in pattern
function replaceFilenameTokens(pattern, next) {
if (pattern.match(/%[bf]/)) {
if (typeof source !== 'string') {
return next(new Error('Cannot replace %f or %b when using an input stream'));
}
pattern = pattern
.replace(/%f/g, path.basename(source))
.replace(/%b/g, path.basename(source, path.extname(source)));
}
next(null, pattern);
},
// Compute size if needed
function getSize(pattern, next) {
if (pattern.match(/%[whr]/)) {
if (fixedSize) {
return next(null, pattern, fixedSize[1], fixedSize[2]);
}
getMetadata(function(err, meta) {
if (err) {
return next(new Error('Could not determine video resolution to replace %w, %h or %r'));
}
var vstream = meta.streams.reduce(function(biggest, stream) {
if (stream.codec_type === 'video' && stream.width * stream.height > biggest.width * biggest.height) {
return stream;
} else {
return biggest;
}
}, { width: 0, height: 0 });
if (vstream.width === 0) {
return next(new Error('No video stream in input, cannot replace %w, %h or %r'));
}
var width = vstream.width;
var height = vstream.height;
if (fixedWidth) {
height = height * Number(fixedWidth[1]) / width;
width = Number(fixedWidth[1]);
} else if (fixedHeight) {
width = width * Number(fixedHeight[1]) / height;
height = Number(fixedHeight[1]);
} else if (percentSize) {
width = width * Number(percentSize[1]) / 100;
height = height * Number(percentSize[1]) / 100;
}
next(null, pattern, Math.round(width / 2) * 2, Math.round(height / 2) * 2);
});
} else {
next(null, pattern, -1, -1);
}
},
// Replace size tokens (%w, %h, %r) in pattern
function replaceSizeTokens(pattern, width, height, next) {
pattern = pattern
.replace(/%r/g, '%wx%h')
.replace(/%w/g, width)
.replace(/%h/g, height);
next(null, pattern);
},
// Replace variable tokens in pattern (%s, %i) and generate filename list
function replaceVariableTokens(pattern, next) {
var filenames = config.timemarks.map(function(t, i) {
return pattern
.replace(/%s/g, utils.timemarkToSeconds(t))
.replace(/%(0*)i/g, function(match, padding) {
var idx = '' + (i + 1);
return padding.substr(0, Math.max(0, padding.length + 1 - idx.length)) + idx;
});
});
self.emit('filenames', filenames);
next(null, filenames);
},
// Create output directory
function createDirectory(filenames, next) {
fs.exists(config.folder, function(exists) {
if (!exists) {
fs.mkdir(config.folder, function(err) {
if (err) {
next(err);
} else {
next(null, filenames);
}
});
} else {
next(null, filenames);
}
});
}
], function runCommand(err, filenames) {
if (err) {
return self.emit('error', err);
}
var count = config.timemarks.length;
var split;
var filters = [split = {
filter: 'split',
options: count,
outputs: []
}];
if ('size' in config) {
// Set size to generate size filters
self.size(config.size);
// Get size filters and chain them with 'sizeN' stream names
var sizeFilters = self._currentOutput.sizeFilters.get().map(function(f, i) {
if (i > 0) {
f.inputs = 'size' + (i - 1);
}
f.outputs = 'size' + i;
return f;
});
// Input last size filter output into split filter
split.inputs = 'size' + (sizeFilters.length - 1);
// Add size filters in front of split filter
filters = sizeFilters.concat(filters);
// Remove size filters
self._currentOutput.sizeFilters.clear();
}
var first = 0;
for (var i = 0; i < count; i++) {
var stream = 'screen' + i;
split.outputs.push(stream);
if (i === 0) {
first = config.timemarks[i];
self.seekInput(first);
}
self.output(path.join(config.folder, filenames[i]))
.frames(1)
.map(stream);
if (i > 0) {
self.seek(config.timemarks[i] - first);
}
}
self.complexFilter(filters);
self.run();
});
return this;
};
/**
* Merge (concatenate) inputs to a single file
*
* @method FfmpegCommand#concat
* @category Processing
* @aliases concatenate,mergeToFile
*
* @param {String|Writable} target output file or writable stream
* @param {Object} [options] pipe options (only used when outputting to a writable stream)
* @return FfmpegCommand
*/
proto.mergeToFile =
proto.concatenate =
proto.concat = function(target, options) {
// Find out which streams are present in the first non-stream input
var fileInput = this._inputs.filter(function(input) {
return !input.isStream;
})[0];
var self = this;
this.ffprobe(this._inputs.indexOf(fileInput), function(err, data) {
if (err) {
return self.emit('error', err);
}
var hasAudioStreams = data.streams.some(function(stream) {
return stream.codec_type === 'audio';
});
var hasVideoStreams = data.streams.some(function(stream) {
return stream.codec_type === 'video';
});
// Setup concat filter and start processing
self.output(target, options)
.complexFilter({
filter: 'concat',
options: {
n: self._inputs.length,
v: hasVideoStreams ? 1 : 0,
a: hasAudioStreams ? 1 : 0
}
})
.run();
});
return this;
};
};