minimagick/lib/mini_magick/image.rb at master · Uelb/minimagick

Repository navigation

History

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

402

403

404

405

406

407

408

409

410

411

412

413

414

415

416

417

418

419

420

421

422

423

424

425

426

427

428

429

430

431

432

433

434

435

436

437

438

439

440

441

442

443

444

445

446

447

448

449

450

451

452

453

454

455

456

457

458

459

460

461

462

463

464

465

466

467

468

469

470

471

472

473

474

475

476

477

478

479

480

481

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

499

500

501

502

503

504

505

506

507

508

509

510

511

512

513

514

515

516

517

518

519

520

521

522

523

524

525

526

527

528

529

530

531

532

533

534

535

536

537

538

539

540

541

542

543

544

545

546

547

548

549

550

551

552

553

554

555

556

557

558

559

560

561

562

563

564

565

566

567

568

569

570

571

572

573

574

575

576

577

578

require 'tempfile'

require 'stringio'

require 'pathname'

require 'uri'

require 'open-uri'

require 'mini_magick/image/info'

require 'mini_magick/utilities'

module MiniMagick

class Image

# This is the primary loading method used by all of the other class

# methods.

# Use this to pass in a stream object. Must respond to #read(size) or be a

# binary string object (BLOBBBB)

# Probably easier to use the {.open} method if you want to open a file or a

# URL.

# @param stream [#read, String] Some kind of stream object that needs

# to be read or is a binary String blob

# @param ext [String] A manual extension to use for reading the file. Not

# required, but if you are having issues, give this a try.

# @return [MiniMagick::Image]

def self.read(stream, ext = nil)

if stream.is_a?(String)

stream = StringIO.new(stream)

end

create(ext) { |file| IO.copy_stream(stream, file) }

end

# Creates an image object from a binary string blob which contains raw

# pixel data (i.e. no header data).

# @param blob [String] Binary string blob containing raw pixel data.

# @param columns [Integer] Number of columns.

# @param rows [Integer] Number of rows.

# @param depth [Integer] Bit depth of the encoded pixel data.

# @param map [String] A code for the mapping of the pixel data. Example:

# 'gray' or 'rgb'.

# @param format [String] The file extension of the image format to be

# used when creating the image object.

# Defaults to 'png'.

# @return [MiniMagick::Image] The loaded image.

def self.import_pixels(blob, columns, rows, depth, map, format = 'png')

# Create an image object with the raw pixel data string:

create(".dat", false) { |f| f.write(blob) }.tap do |image|

output_path = image.path.sub(/\.\w+$/, ".#{format}")

# Use ImageMagick to convert the raw data file to an image file of the

# desired format:

MiniMagick::Tool::Convert.new do |convert|

convert.size "#{columns}x#{rows}"

convert.depth depth

convert << "#{map}:#{image.path}"

convert << output_path

end

image.path.replace output_path

end

# Opens a specific image file either on the local file system or at a URI.

# Use this if you don't want to overwrite the image file.

# Extension is either guessed from the path or you can specify it as a

# second parameter.

# @param path_or_url [String] Either a local file path or a URL that

# open-uri can read

# @param ext [String] Specify the extension you want to read it as

# @param options [Hash] Specify options for the open method

# @return [MiniMagick::Image] The loaded image

def self.open(path_or_url, ext = nil, options = {})

options, ext = ext, nil if ext.is_a?(Hash)

ext ||=

if File.exist?(path_or_url)

File.extname(path_or_url)

else

File.extname(URI(path_or_url).path)

end

ext.sub!(/:.*/, '') # hack for filenames or URLs that include a colon

Kernel.open(path_or_url, "rb", options) do |file|

read(file, ext)

end

# Used to create a new Image object data-copy. Not used to "paint" or

# that kind of thing.

# Takes an extension in a block and can be used to build a new Image

# object. Used by both {.open} and {.read} to create a new object. Ensures

# we have a good tempfile.

# @param ext [String] Specify the extension you want to read it as

# @param validate [Boolean] If false, skips validation of the created

# image. Defaults to true.

# @yield [Tempfile] You can #write bits to this object to create the new

# Image

# @return [MiniMagick::Image] The created image

def self.create(ext = nil, validate = MiniMagick.validate_on_create, &block)

tempfile = MiniMagick::Utilities.tempfile(ext.to_s.downcase, &block)

new(tempfile.path, tempfile).tap do |image|

image.validate! if validate

end

# @private

# @!macro [attach] attribute

# @!attribute [r] $1

def self.attribute(name, key = name.to_s)

define_method(name) do |*args|

if args.any? && name != :resolution

mogrify { |b| b.send(name, *args) }

else

@info[key, *args]

end

# @return [String] The location of the current working file

attr_reader :path

# @return [Tempfile] The underlying temporary file

attr_reader :tempfile

# Create a new {MiniMagick::Image} object.

# _DANGER_: The file location passed in here is the *working copy*. That

# is, it gets *modified*. You can either copy it yourself or use {.open}

# which creates a temporary file for you and protects your original.

# @param input_path [String, Pathname] The location of an image file

# @yield [MiniMagick::Tool::Mogrify] If block is given, {#combine_options}

# is called.

def initialize(input_path, tempfile = nil, &block)

@path = input_path.to_s

@tempfile = tempfile

@info = MiniMagick::Image::Info.new(@path)

combine_options(&block) if block

end

def ==(other)

self.class == other.class && signature == other.signature

end

alias eql? ==

def hash

signature.hash

end

# Returns raw image data.

# @return [String] Binary string

def to_blob

File.binread(path)

end

# Checks to make sure that MiniMagick can read the file and understand it.

# This uses the 'identify' command line utility to check the file. If you

# are having issues with this, then please work directly with the

# 'identify' command and see if you can figure out what the issue is.

# @return [Boolean]

def valid?

validate!

true

rescue MiniMagick::Invalid

false

end

# Runs `identify` on the current image, and raises an error if it doesn't

# pass.

# @raise [MiniMagick::Invalid]

def validate!

identify

rescue MiniMagick::Error => error

raise MiniMagick::Invalid, error.message

end

# Returns the image format (e.g. "JPEG", "GIF").

# @return [String]

attribute :type, "format"

# @return [String]

attribute :mime_type

# @return [Integer]

attribute :width

# @return [Integer]

attribute :height

# @return [Array<Integer>]

attribute :dimensions

# Returns the file size of the image (in bytes).

# @return [Integer]

attribute :size

# Returns the file size in a human readable format.

# @return [String]

attribute :human_size

# @return [String]

attribute :colorspace

# @return [Hash]

attribute :exif

# Returns the resolution of the photo. You can optionally specify the

# units measurement.

# @example

# image.resolution("PixelsPerInch") #=> [250, 250]

# @see http://www.imagemagick.org/script/command-line-options.php#units

# @return [Array<Integer>]

attribute :resolution

# Returns the message digest of this image as a SHA-256, hexidecimal

# encoded string. This signature uniquely identifies the image and is

# convenient for determining if an image has been modified or whether two

# images are identical.

# @example

# image.signature #=> "60a7848c4ca6e36b8e2c5dea632ecdc29e9637791d2c59ebf7a54c0c6a74ef7e"

# @see http://www.imagemagick.org/api/signature.php

# @return [String]

attribute :signature

# Returns the information from `identify -verbose` in a Hash format, for

# ImageMagick.

# @return [Hash]

attribute :data

# Returns the information from `identify -verbose` in a Hash format, for

# GraphicsMagick.

# @return [Hash]

attribute :details

# Use this method if you want to access raw Identify's format API.

# @example

# image["%w %h"] #=> "250 450"

# image["%r"] #=> "DirectClass sRGB"

# @param value [String]

# @see http://www.imagemagick.org/script/escape.php

# @return [String]

def [](value)

@info[value.to_s]

end

alias info []

# Returns layers of the image. For example, JPEGs are 1-layered, but

# formats like PSDs, GIFs and PDFs can have multiple layers/frames/pages.

# @example

# image = MiniMagick::Image.new("document.pdf")

# image.pages.each_with_index do |page, idx|

# page.write("page#{idx}.pdf")

# end

# @return [Array<MiniMagick::Image>]

def layers

layers_count = identify.lines.count

layers_count.times.map do |idx|

MiniMagick::Image.new("#{path}[#{idx}]")

end

alias pages layers

alias frames layers

# Returns a matrix of pixels from the image. The matrix is constructed as

# an array (1) of arrays (2) of arrays (3) of unsigned integers:

# 1) one for each row of pixels

# 2) one for each column of pixels

# 3) three elements in the range 0-255, one for each of the RGB color channels

# @example

# img = MiniMagick::Image.open 'image.jpg'

# pixels = img.get_pixels

# pixels[3][2][1] # the green channel value from the 4th-row, 3rd-column pixel

# It can also be called after applying transformations:

# @example

# img = MiniMagick::Image.open 'image.jpg'

# img.crop '20x30+10+5'

# img.colorspace 'Gray'

# pixels = img.get_pixels

# In this example, all pixels in pix should now have equal R, G, and B values.

# @return [Array] Matrix of each color of each pixel

def get_pixels

convert = MiniMagick::Tool::Convert.new

convert << path

convert.depth(8)

convert << "RGB:-"

# Do not use `convert.call` here. We need the whole binary (unstripped) output here.

shell = MiniMagick::Shell.new

output, * = shell.run(convert.command)

pixels_array = output.unpack("C*")

pixels = pixels_array.each_slice(3).each_slice(width).to_a

# deallocate large intermediary objects

output.clear

pixels_array.clear

pixels

end

# This is used to change the format of the image. That is, from "tiff to

# jpg" or something like that. Once you run it, the instance is pointing to

# a new file with a new extension!

# *DANGER*: This renames the file that the instance is pointing to. So, if

# you manually opened the file with Image.new(file_path)... Then that file

# is DELETED! If you used Image.open(file) then you are OK. The original

# file will still be there. But, any changes to it might not be...

# Formatting an animation into a non-animated type will result in

# ImageMagick creating multiple pages (starting with 0). You can choose

# which page you want to manipulate. We default to the first page.

# If you would like to convert between animated formats, pass nil as your

# page and ImageMagick will copy all of the pages.

# @param format [String] The target format... Like 'jpg', 'gif', 'tiff' etc.

# @param page [Integer] If this is an animated gif, say which 'page' you

# want with an integer. Default 0 will convert only the first page; 'nil'

# will convert all pages.

# @param read_opts [Hash] Any read options to be passed to ImageMagick

# for example: image.format('jpg', page, {density: '300'})

# @yield [MiniMagick::Tool::Convert] It optionally yields the command,

# if you want to add something.

# @return [self]

def format(format, page = 0, read_opts={})

if @tempfile

new_tempfile = MiniMagick::Utilities.tempfile(".#{format}")

new_path = new_tempfile.path

else

new_path = Pathname(path).sub_ext(".#{format}").to_s

end

input_path = path.dup

input_path << "[#{page}]" if page && !layer?

MiniMagick::Tool::Convert.new do |convert|

read_opts.each do |opt, val|

convert.send(opt.to_s, val)

end

convert << input_path

yield convert if block_given?

convert << new_path

end

if @tempfile

destroy!

@tempfile = new_tempfile

else

File.delete(path) unless path == new_path || layer?

end

path.replace new_path

@info.clear

self

end

# You can use multiple commands together using this method. Very easy to

# use!

# @example

# image.combine_options do |c|

# c.draw "image Over 0,0 10,10 '#{MINUS_IMAGE_PATH}'"

# c.thumbnail "300x500>"

# c.background "blue"

# end

# @yield [MiniMagick::Tool::Mogrify]

# @see http://www.imagemagick.org/script/mogrify.php

# @return [self]

def combine_options(&block)

mogrify(&block)

end

# If an unknown method is called then it is sent through the mogrify

# program.

# @see http://www.imagemagick.org/script/mogrify.php

# @return [self]

def method_missing(name, *args)

mogrify do |builder|

builder.send(name, *args)

end

def respond_to_missing?(method_name, include_private = false)

MiniMagick::Tool::Mogrify.option_methods.include?(method_name.to_s)

end

# Writes the temporary file out to either a file location (by passing in a

# String) or by passing in a Stream that you can #write(chunk) to

# repeatedly

# @param output_to [String, Pathname, #read] Some kind of stream object

# that needs to be read or a file path as a String

def write(output_to)

case output_to

when String, Pathname

if layer?

MiniMagick::Tool::Convert.new do |builder|

builder << path

builder << output_to

end

else

FileUtils.copy_file path, output_to unless path == output_to.to_s

end

else

IO.copy_stream File.open(path, "rb"), output_to

end

# @example

# first_image = MiniMagick::Image.open "first.jpg"

# second_image = MiniMagick::Image.open "second.jpg"

# result = first_image.composite(second_image) do |c|

# c.compose "Over" # OverCompositeOp

# c.geometry "+20+20" # copy second_image onto first_image from (20, 20)

# end

# result.write "output.jpg"

# @see http://www.imagemagick.org/script/composite.php

def composite(other_image, output_extension = type.downcase, mask = nil)

output_tempfile = MiniMagick::Utilities.tempfile(".#{output_extension}")

MiniMagick::Tool::Composite.new do |composite|

yield composite if block_given?

composite << other_image.path

composite << path

composite << mask.path if mask

composite << output_tempfile.path

end

Image.new(output_tempfile.path, output_tempfile)

end

# Collapse images with sequences to the first frame (i.e. animated gifs) and

# preserve quality.

# @param frame [Integer] The frame to which to collapse to, defaults to `0`.

# @return [self]

def collapse!(frame = 0)

mogrify(frame) { |builder| builder.quality(100) }

end

# Destroys the tempfile (created by {.open}) if it exists.

def destroy!

if @tempfile

FileUtils.rm_f @tempfile.path.sub(/mpc$/, "cache") if @tempfile.path.end_with?(".mpc")

@tempfile.unlink

end

# Runs `identify` on itself. Accepts an optional block for adding more

# options to `identify`.

# @example

# image = MiniMagick::Image.open("image.jpg")

# image.identify do |b|

# b.verbose

# end # runs `identify -verbose image.jpg`

# @return [String] Output from `identify`

# @yield [MiniMagick::Tool::Identify]

def identify

MiniMagick::Tool::Identify.new do |builder|

yield builder if block_given?

builder << path

end

# @private

def run_command(tool_name, *args)

MiniMagick::Tool.const_get(tool_name.capitalize).new do |builder|

args.each do |arg|

builder << arg

end

def mogrify(page = nil)

MiniMagick::Tool::MogrifyRestricted.new do |builder|

yield builder if block_given?

builder << (page ? "#{path}[#{page}]" : path)

end

@info.clear

self

end

def layer?

path =~ /\[\d+\]$/

end

FilesExpand file tree

image.rb

Latest commit

History

image.rb

File metadata and controls