• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2007 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.graphics;
18 
19 import static android.graphics.BitmapFactory.Options.validate;
20 
21 import android.content.res.AssetManager;
22 import android.content.res.Resources;
23 import android.os.Trace;
24 import android.util.DisplayMetrics;
25 import android.util.Log;
26 import android.util.TypedValue;
27 
28 import java.io.FileDescriptor;
29 import java.io.FileInputStream;
30 import java.io.IOException;
31 import java.io.InputStream;
32 
33 /**
34  * Creates Bitmap objects from various sources, including files, streams,
35  * and byte-arrays.
36  */
37 public class BitmapFactory {
38     private static final int DECODE_BUFFER_SIZE = 16 * 1024;
39 
40     public static class Options {
41         /**
42          * Create a default Options object, which if left unchanged will give
43          * the same result from the decoder as if null were passed.
44          */
Options()45         public Options() {
46             inScaled = true;
47             inPremultiplied = true;
48         }
49 
50         /**
51          * If set, decode methods that take the Options object will attempt to
52          * reuse this bitmap when loading content. If the decode operation
53          * cannot use this bitmap, the decode method will throw an
54          * {@link java.lang.IllegalArgumentException}. The
55          * current implementation necessitates that the reused bitmap be
56          * mutable, and the resulting reused bitmap will continue to remain
57          * mutable even when decoding a resource which would normally result in
58          * an immutable bitmap.</p>
59          *
60          * <p>You should still always use the returned Bitmap of the decode
61          * method and not assume that reusing the bitmap worked, due to the
62          * constraints outlined above and failure situations that can occur.
63          * Checking whether the return value matches the value of the inBitmap
64          * set in the Options structure will indicate if the bitmap was reused,
65          * but in all cases you should use the Bitmap returned by the decoding
66          * function to ensure that you are using the bitmap that was used as the
67          * decode destination.</p>
68          *
69          * <h3>Usage with BitmapFactory</h3>
70          *
71          * <p>As of {@link android.os.Build.VERSION_CODES#KITKAT}, any
72          * mutable bitmap can be reused by {@link BitmapFactory} to decode any
73          * other bitmaps as long as the resulting {@link Bitmap#getByteCount()
74          * byte count} of the decoded bitmap is less than or equal to the {@link
75          * Bitmap#getAllocationByteCount() allocated byte count} of the reused
76          * bitmap. This can be because the intrinsic size is smaller, or its
77          * size post scaling (for density / sample size) is smaller.</p>
78          *
79          * <p class="note">Prior to {@link android.os.Build.VERSION_CODES#KITKAT}
80          * additional constraints apply: The image being decoded (whether as a
81          * resource or as a stream) must be in jpeg or png format. Only equal
82          * sized bitmaps are supported, with {@link #inSampleSize} set to 1.
83          * Additionally, the {@link android.graphics.Bitmap.Config
84          * configuration} of the reused bitmap will override the setting of
85          * {@link #inPreferredConfig}, if set.</p>
86          *
87          * <h3>Usage with BitmapRegionDecoder</h3>
88          *
89          * <p>BitmapRegionDecoder will draw its requested content into the Bitmap
90          * provided, clipping if the output content size (post scaling) is larger
91          * than the provided Bitmap. The provided Bitmap's width, height, and
92          * {@link Bitmap.Config} will not be changed.
93          *
94          * <p class="note">BitmapRegionDecoder support for {@link #inBitmap} was
95          * introduced in {@link android.os.Build.VERSION_CODES#JELLY_BEAN}. All
96          * formats supported by BitmapRegionDecoder support Bitmap reuse via
97          * {@link #inBitmap}.</p>
98          *
99          * @see Bitmap#reconfigure(int,int, android.graphics.Bitmap.Config)
100          */
101         public Bitmap inBitmap;
102 
103         /**
104          * If set, decode methods will always return a mutable Bitmap instead of
105          * an immutable one. This can be used for instance to programmatically apply
106          * effects to a Bitmap loaded through BitmapFactory.
107          * <p>Can not be set simultaneously with inPreferredConfig =
108          * {@link android.graphics.Bitmap.Config#HARDWARE},
109          * because hardware bitmaps are always immutable.
110          */
111         @SuppressWarnings({"UnusedDeclaration"}) // used in native code
112         public boolean inMutable;
113 
114         /**
115          * If set to true, the decoder will return null (no bitmap), but
116          * the <code>out...</code> fields will still be set, allowing the caller to
117          * query the bitmap without having to allocate the memory for its pixels.
118          */
119         public boolean inJustDecodeBounds;
120 
121         /**
122          * If set to a value > 1, requests the decoder to subsample the original
123          * image, returning a smaller image to save memory. The sample size is
124          * the number of pixels in either dimension that correspond to a single
125          * pixel in the decoded bitmap. For example, inSampleSize == 4 returns
126          * an image that is 1/4 the width/height of the original, and 1/16 the
127          * number of pixels. Any value <= 1 is treated the same as 1. Note: the
128          * decoder uses a final value based on powers of 2, any other value will
129          * be rounded down to the nearest power of 2.
130          */
131         public int inSampleSize;
132 
133         /**
134          * If this is non-null, the decoder will try to decode into this
135          * internal configuration. If it is null, or the request cannot be met,
136          * the decoder will try to pick the best matching config based on the
137          * system's screen depth, and characteristics of the original image such
138          * as if it has per-pixel alpha (requiring a config that also does).
139          *
140          * Image are loaded with the {@link Bitmap.Config#ARGB_8888} config by
141          * default.
142          */
143         public Bitmap.Config inPreferredConfig = Bitmap.Config.ARGB_8888;
144 
145         /**
146          * <p>If this is non-null, the decoder will try to decode into this
147          * color space. If it is null, or the request cannot be met,
148          * the decoder will pick either the color space embedded in the image
149          * or the color space best suited for the requested image configuration
150          * (for instance {@link ColorSpace.Named#SRGB sRGB} for
151          * the {@link Bitmap.Config#ARGB_8888} configuration).</p>
152          *
153          * <p>{@link Bitmap.Config#RGBA_F16} always uses the
154          * {@link ColorSpace.Named#LINEAR_EXTENDED_SRGB scRGB} color space).
155          * Bitmaps in other configurations without an embedded color space are
156          * assumed to be in the {@link ColorSpace.Named#SRGB sRGB} color space.</p>
157          *
158          * <p class="note">Only {@link ColorSpace.Model#RGB} color spaces are
159          * currently supported. An <code>IllegalArgumentException</code> will
160          * be thrown by the decode methods when setting a non-RGB color space
161          * such as {@link ColorSpace.Named#CIE_LAB Lab}.</p>
162          *
163          * <p class="note">The specified color space's transfer function must be
164          * an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}. An
165          * <code>IllegalArgumentException</code> will be thrown by the decode methods
166          * if calling {@link ColorSpace.Rgb#getTransferParameters()} on the
167          * specified color space returns null.</p>
168          *
169          * <p>After decode, the bitmap's color space is stored in
170          * {@link #outColorSpace}.</p>
171          */
172         public ColorSpace inPreferredColorSpace = null;
173 
174         /**
175          * If true (which is the default), the resulting bitmap will have its
176          * color channels pre-multipled by the alpha channel.
177          *
178          * <p>This should NOT be set to false for images to be directly drawn by
179          * the view system or through a {@link Canvas}. The view system and
180          * {@link Canvas} assume all drawn images are pre-multiplied to simplify
181          * draw-time blending, and will throw a RuntimeException when
182          * un-premultiplied are drawn.</p>
183          *
184          * <p>This is likely only useful if you want to manipulate raw encoded
185          * image data, e.g. with RenderScript or custom OpenGL.</p>
186          *
187          * <p>This does not affect bitmaps without an alpha channel.</p>
188          *
189          * <p>Setting this flag to false while setting {@link #inScaled} to true
190          * may result in incorrect colors.</p>
191          *
192          * @see Bitmap#hasAlpha()
193          * @see Bitmap#isPremultiplied()
194          * @see #inScaled
195          */
196         public boolean inPremultiplied;
197 
198         /**
199          * @deprecated As of {@link android.os.Build.VERSION_CODES#N}, this is
200          * ignored.
201          *
202          * In {@link android.os.Build.VERSION_CODES#M} and below, if dither is
203          * true, the decoder will attempt to dither the decoded image.
204          */
205         public boolean inDither;
206 
207         /**
208          * The pixel density to use for the bitmap.  This will always result
209          * in the returned bitmap having a density set for it (see
210          * {@link Bitmap#setDensity(int) Bitmap.setDensity(int)}).  In addition,
211          * if {@link #inScaled} is set (which it is by default} and this
212          * density does not match {@link #inTargetDensity}, then the bitmap
213          * will be scaled to the target density before being returned.
214          *
215          * <p>If this is 0,
216          * {@link BitmapFactory#decodeResource(Resources, int)},
217          * {@link BitmapFactory#decodeResource(Resources, int, android.graphics.BitmapFactory.Options)},
218          * and {@link BitmapFactory#decodeResourceStream}
219          * will fill in the density associated with the resource.  The other
220          * functions will leave it as-is and no density will be applied.
221          *
222          * @see #inTargetDensity
223          * @see #inScreenDensity
224          * @see #inScaled
225          * @see Bitmap#setDensity(int)
226          * @see android.util.DisplayMetrics#densityDpi
227          */
228         public int inDensity;
229 
230         /**
231          * The pixel density of the destination this bitmap will be drawn to.
232          * This is used in conjunction with {@link #inDensity} and
233          * {@link #inScaled} to determine if and how to scale the bitmap before
234          * returning it.
235          *
236          * <p>If this is 0,
237          * {@link BitmapFactory#decodeResource(Resources, int)},
238          * {@link BitmapFactory#decodeResource(Resources, int, android.graphics.BitmapFactory.Options)},
239          * and {@link BitmapFactory#decodeResourceStream}
240          * will fill in the density associated the Resources object's
241          * DisplayMetrics.  The other
242          * functions will leave it as-is and no scaling for density will be
243          * performed.
244          *
245          * @see #inDensity
246          * @see #inScreenDensity
247          * @see #inScaled
248          * @see android.util.DisplayMetrics#densityDpi
249          */
250         public int inTargetDensity;
251 
252         /**
253          * The pixel density of the actual screen that is being used.  This is
254          * purely for applications running in density compatibility code, where
255          * {@link #inTargetDensity} is actually the density the application
256          * sees rather than the real screen density.
257          *
258          * <p>By setting this, you
259          * allow the loading code to avoid scaling a bitmap that is currently
260          * in the screen density up/down to the compatibility density.  Instead,
261          * if {@link #inDensity} is the same as {@link #inScreenDensity}, the
262          * bitmap will be left as-is.  Anything using the resulting bitmap
263          * must also used {@link Bitmap#getScaledWidth(int)
264          * Bitmap.getScaledWidth} and {@link Bitmap#getScaledHeight
265          * Bitmap.getScaledHeight} to account for any different between the
266          * bitmap's density and the target's density.
267          *
268          * <p>This is never set automatically for the caller by
269          * {@link BitmapFactory} itself.  It must be explicitly set, since the
270          * caller must deal with the resulting bitmap in a density-aware way.
271          *
272          * @see #inDensity
273          * @see #inTargetDensity
274          * @see #inScaled
275          * @see android.util.DisplayMetrics#densityDpi
276          */
277         public int inScreenDensity;
278 
279         /**
280          * When this flag is set, if {@link #inDensity} and
281          * {@link #inTargetDensity} are not 0, the
282          * bitmap will be scaled to match {@link #inTargetDensity} when loaded,
283          * rather than relying on the graphics system scaling it each time it
284          * is drawn to a Canvas.
285          *
286          * <p>BitmapRegionDecoder ignores this flag, and will not scale output
287          * based on density. (though {@link #inSampleSize} is supported)</p>
288          *
289          * <p>This flag is turned on by default and should be turned off if you need
290          * a non-scaled version of the bitmap.  Nine-patch bitmaps ignore this
291          * flag and are always scaled.
292          *
293          * <p>If {@link #inPremultiplied} is set to false, and the image has alpha,
294          * setting this flag to true may result in incorrect colors.
295          */
296         public boolean inScaled;
297 
298         /**
299          * @deprecated As of {@link android.os.Build.VERSION_CODES#LOLLIPOP}, this is
300          * ignored.
301          *
302          * In {@link android.os.Build.VERSION_CODES#KITKAT} and below, if this
303          * is set to true, then the resulting bitmap will allocate its
304          * pixels such that they can be purged if the system needs to reclaim
305          * memory. In that instance, when the pixels need to be accessed again
306          * (e.g. the bitmap is drawn, getPixels() is called), they will be
307          * automatically re-decoded.
308          *
309          * <p>For the re-decode to happen, the bitmap must have access to the
310          * encoded data, either by sharing a reference to the input
311          * or by making a copy of it. This distinction is controlled by
312          * inInputShareable. If this is true, then the bitmap may keep a shallow
313          * reference to the input. If this is false, then the bitmap will
314          * explicitly make a copy of the input data, and keep that. Even if
315          * sharing is allowed, the implementation may still decide to make a
316          * deep copy of the input data.</p>
317          *
318          * <p>While inPurgeable can help avoid big Dalvik heap allocations (from
319          * API level 11 onward), it sacrifices performance predictability since any
320          * image that the view system tries to draw may incur a decode delay which
321          * can lead to dropped frames. Therefore, most apps should avoid using
322          * inPurgeable to allow for a fast and fluid UI. To minimize Dalvik heap
323          * allocations use the {@link #inBitmap} flag instead.</p>
324          *
325          * <p class="note"><strong>Note:</strong> This flag is ignored when used
326          * with {@link #decodeResource(Resources, int,
327          * android.graphics.BitmapFactory.Options)} or {@link #decodeFile(String,
328          * android.graphics.BitmapFactory.Options)}.</p>
329          */
330         @Deprecated
331         public boolean inPurgeable;
332 
333         /**
334          * @deprecated As of {@link android.os.Build.VERSION_CODES#LOLLIPOP}, this is
335          * ignored.
336          *
337          * In {@link android.os.Build.VERSION_CODES#KITKAT} and below, this
338          * field works in conjuction with inPurgeable. If inPurgeable is false,
339          * then this field is ignored. If inPurgeable is true, then this field
340          * determines whether the bitmap can share a reference to the input
341          * data (inputstream, array, etc.) or if it must make a deep copy.
342          */
343         @Deprecated
344         public boolean inInputShareable;
345 
346         /**
347          * @deprecated As of {@link android.os.Build.VERSION_CODES#N}, this is
348          * ignored.  The output will always be high quality.
349          *
350          * In {@link android.os.Build.VERSION_CODES#M} and below, if
351          * inPreferQualityOverSpeed is set to true, the decoder will try to
352          * decode the reconstructed image to a higher quality even at the
353          * expense of the decoding speed. Currently the field only affects JPEG
354          * decode, in the case of which a more accurate, but slightly slower,
355          * IDCT method will be used instead.
356          */
357         public boolean inPreferQualityOverSpeed;
358 
359         /**
360          * The resulting width of the bitmap. If {@link #inJustDecodeBounds} is
361          * set to false, this will be width of the output bitmap after any
362          * scaling is applied. If true, it will be the width of the input image
363          * without any accounting for scaling.
364          *
365          * <p>outWidth will be set to -1 if there is an error trying to decode.</p>
366          */
367         public int outWidth;
368 
369         /**
370          * The resulting height of the bitmap. If {@link #inJustDecodeBounds} is
371          * set to false, this will be height of the output bitmap after any
372          * scaling is applied. If true, it will be the height of the input image
373          * without any accounting for scaling.
374          *
375          * <p>outHeight will be set to -1 if there is an error trying to decode.</p>
376          */
377         public int outHeight;
378 
379         /**
380          * If known, this string is set to the mimetype of the decoded image.
381          * If not known, or there is an error, it is set to null.
382          */
383         public String outMimeType;
384 
385         /**
386          * If known, the config the decoded bitmap will have.
387          * If not known, or there is an error, it is set to null.
388          */
389         public Bitmap.Config outConfig;
390 
391         /**
392          * If known, the color space the decoded bitmap will have. Note that the
393          * output color space is not guaranteed to be the color space the bitmap
394          * is encoded with. If not known (when the config is
395          * {@link Bitmap.Config#ALPHA_8} for instance), or there is an error,
396          * it is set to null.
397          */
398         public ColorSpace outColorSpace;
399 
400         /**
401          * Temp storage to use for decoding.  Suggest 16K or so.
402          */
403         public byte[] inTempStorage;
404 
405         /**
406          * @deprecated As of {@link android.os.Build.VERSION_CODES#N}, see
407          * comments on {@link #requestCancelDecode()}.
408          *
409          * Flag to indicate that cancel has been called on this object.  This
410          * is useful if there's an intermediary that wants to first decode the
411          * bounds and then decode the image.  In that case the intermediary
412          * can check, inbetween the bounds decode and the image decode, to see
413          * if the operation is canceled.
414          */
415         public boolean mCancel;
416 
417         /**
418          *  @deprecated As of {@link android.os.Build.VERSION_CODES#N}, this
419          *  will not affect the decode, though it will still set mCancel.
420          *
421          *  In {@link android.os.Build.VERSION_CODES#M} and below, if this can
422          *  be called from another thread while this options object is inside
423          *  a decode... call. Calling this will notify the decoder that it
424          *  should cancel its operation. This is not guaranteed to cancel the
425          *  decode, but if it does, the decoder... operation will return null,
426          *  or if inJustDecodeBounds is true, will set outWidth/outHeight
427          *  to -1
428          */
requestCancelDecode()429         public void requestCancelDecode() {
430             mCancel = true;
431         }
432 
validate(Options opts)433         static void validate(Options opts) {
434             if (opts == null) return;
435 
436             if (opts.inBitmap != null && opts.inBitmap.getConfig() == Bitmap.Config.HARDWARE) {
437                 throw new IllegalArgumentException("Bitmaps with Config.HARWARE are always immutable");
438             }
439 
440             if (opts.inMutable && opts.inPreferredConfig == Bitmap.Config.HARDWARE) {
441                 throw new IllegalArgumentException("Bitmaps with Config.HARDWARE cannot be " +
442                         "decoded into - they are immutable");
443             }
444 
445             if (opts.inPreferredColorSpace != null) {
446                 if (!(opts.inPreferredColorSpace instanceof ColorSpace.Rgb)) {
447                     throw new IllegalArgumentException("The destination color space must use the " +
448                             "RGB color model");
449                 }
450                 if (((ColorSpace.Rgb) opts.inPreferredColorSpace).getTransferParameters() == null) {
451                     throw new IllegalArgumentException("The destination color space must use an " +
452                             "ICC parametric transfer function");
453                 }
454             }
455         }
456     }
457 
458     /**
459      * Decode a file path into a bitmap. If the specified file name is null,
460      * or cannot be decoded into a bitmap, the function returns null.
461      *
462      * @param pathName complete path name for the file to be decoded.
463      * @param opts null-ok; Options that control downsampling and whether the
464      *             image should be completely decoded, or just is size returned.
465      * @return The decoded bitmap, or null if the image data could not be
466      *         decoded, or, if opts is non-null, if opts requested only the
467      *         size be returned (in opts.outWidth and opts.outHeight)
468      * @throws IllegalArgumentException if {@link BitmapFactory.Options#inPreferredConfig}
469      *         is {@link android.graphics.Bitmap.Config#HARDWARE}
470      *         and {@link BitmapFactory.Options#inMutable} is set, if the specified color space
471      *         is not {@link ColorSpace.Model#RGB RGB}, or if the specified color space's transfer
472      *         function is not an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}
473      */
decodeFile(String pathName, Options opts)474     public static Bitmap decodeFile(String pathName, Options opts) {
475         validate(opts);
476         Bitmap bm = null;
477         InputStream stream = null;
478         try {
479             stream = new FileInputStream(pathName);
480             bm = decodeStream(stream, null, opts);
481         } catch (Exception e) {
482             /*  do nothing.
483                 If the exception happened on open, bm will be null.
484             */
485             Log.e("BitmapFactory", "Unable to decode stream: " + e);
486         } finally {
487             if (stream != null) {
488                 try {
489                     stream.close();
490                 } catch (IOException e) {
491                     // do nothing here
492                 }
493             }
494         }
495         return bm;
496     }
497 
498     /**
499      * Decode a file path into a bitmap. If the specified file name is null,
500      * or cannot be decoded into a bitmap, the function returns null.
501      *
502      * @param pathName complete path name for the file to be decoded.
503      * @return the resulting decoded bitmap, or null if it could not be decoded.
504      */
decodeFile(String pathName)505     public static Bitmap decodeFile(String pathName) {
506         return decodeFile(pathName, null);
507     }
508 
509     /**
510      * Decode a new Bitmap from an InputStream. This InputStream was obtained from
511      * resources, which we pass to be able to scale the bitmap accordingly.
512      * @throws IllegalArgumentException if {@link BitmapFactory.Options#inPreferredConfig}
513      *         is {@link android.graphics.Bitmap.Config#HARDWARE}
514      *         and {@link BitmapFactory.Options#inMutable} is set, if the specified color space
515      *         is not {@link ColorSpace.Model#RGB RGB}, or if the specified color space's transfer
516      *         function is not an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}
517      */
decodeResourceStream(Resources res, TypedValue value, InputStream is, Rect pad, Options opts)518     public static Bitmap decodeResourceStream(Resources res, TypedValue value,
519             InputStream is, Rect pad, Options opts) {
520         validate(opts);
521         if (opts == null) {
522             opts = new Options();
523         }
524 
525         if (opts.inDensity == 0 && value != null) {
526             final int density = value.density;
527             if (density == TypedValue.DENSITY_DEFAULT) {
528                 opts.inDensity = DisplayMetrics.DENSITY_DEFAULT;
529             } else if (density != TypedValue.DENSITY_NONE) {
530                 opts.inDensity = density;
531             }
532         }
533 
534         if (opts.inTargetDensity == 0 && res != null) {
535             opts.inTargetDensity = res.getDisplayMetrics().densityDpi;
536         }
537 
538         return decodeStream(is, pad, opts);
539     }
540 
541     /**
542      * Synonym for opening the given resource and calling
543      * {@link #decodeResourceStream}.
544      *
545      * @param res   The resources object containing the image data
546      * @param id The resource id of the image data
547      * @param opts null-ok; Options that control downsampling and whether the
548      *             image should be completely decoded, or just is size returned.
549      * @return The decoded bitmap, or null if the image data could not be
550      *         decoded, or, if opts is non-null, if opts requested only the
551      *         size be returned (in opts.outWidth and opts.outHeight)
552      * @throws IllegalArgumentException if {@link BitmapFactory.Options#inPreferredConfig}
553      *         is {@link android.graphics.Bitmap.Config#HARDWARE}
554      *         and {@link BitmapFactory.Options#inMutable} is set, if the specified color space
555      *         is not {@link ColorSpace.Model#RGB RGB}, or if the specified color space's transfer
556      *         function is not an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}
557      */
decodeResource(Resources res, int id, Options opts)558     public static Bitmap decodeResource(Resources res, int id, Options opts) {
559         validate(opts);
560         Bitmap bm = null;
561         InputStream is = null;
562 
563         try {
564             final TypedValue value = new TypedValue();
565             is = res.openRawResource(id, value);
566 
567             bm = decodeResourceStream(res, value, is, null, opts);
568         } catch (Exception e) {
569             /*  do nothing.
570                 If the exception happened on open, bm will be null.
571                 If it happened on close, bm is still valid.
572             */
573         } finally {
574             try {
575                 if (is != null) is.close();
576             } catch (IOException e) {
577                 // Ignore
578             }
579         }
580 
581         if (bm == null && opts != null && opts.inBitmap != null) {
582             throw new IllegalArgumentException("Problem decoding into existing bitmap");
583         }
584 
585         return bm;
586     }
587 
588     /**
589      * Synonym for {@link #decodeResource(Resources, int, android.graphics.BitmapFactory.Options)}
590      * with null Options.
591      *
592      * @param res The resources object containing the image data
593      * @param id The resource id of the image data
594      * @return The decoded bitmap, or null if the image could not be decoded.
595      */
decodeResource(Resources res, int id)596     public static Bitmap decodeResource(Resources res, int id) {
597         return decodeResource(res, id, null);
598     }
599 
600     /**
601      * Decode an immutable bitmap from the specified byte array.
602      *
603      * @param data byte array of compressed image data
604      * @param offset offset into imageData for where the decoder should begin
605      *               parsing.
606      * @param length the number of bytes, beginning at offset, to parse
607      * @param opts null-ok; Options that control downsampling and whether the
608      *             image should be completely decoded, or just is size returned.
609      * @return The decoded bitmap, or null if the image data could not be
610      *         decoded, or, if opts is non-null, if opts requested only the
611      *         size be returned (in opts.outWidth and opts.outHeight)
612      * @throws IllegalArgumentException if {@link BitmapFactory.Options#inPreferredConfig}
613      *         is {@link android.graphics.Bitmap.Config#HARDWARE}
614      *         and {@link BitmapFactory.Options#inMutable} is set, if the specified color space
615      *         is not {@link ColorSpace.Model#RGB RGB}, or if the specified color space's transfer
616      *         function is not an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}
617      */
decodeByteArray(byte[] data, int offset, int length, Options opts)618     public static Bitmap decodeByteArray(byte[] data, int offset, int length, Options opts) {
619         if ((offset | length) < 0 || data.length < offset + length) {
620             throw new ArrayIndexOutOfBoundsException();
621         }
622         validate(opts);
623 
624         Bitmap bm;
625 
626         Trace.traceBegin(Trace.TRACE_TAG_GRAPHICS, "decodeBitmap");
627         try {
628             bm = nativeDecodeByteArray(data, offset, length, opts);
629 
630             if (bm == null && opts != null && opts.inBitmap != null) {
631                 throw new IllegalArgumentException("Problem decoding into existing bitmap");
632             }
633             setDensityFromOptions(bm, opts);
634         } finally {
635             Trace.traceEnd(Trace.TRACE_TAG_GRAPHICS);
636         }
637 
638         return bm;
639     }
640 
641     /**
642      * Decode an immutable bitmap from the specified byte array.
643      *
644      * @param data byte array of compressed image data
645      * @param offset offset into imageData for where the decoder should begin
646      *               parsing.
647      * @param length the number of bytes, beginning at offset, to parse
648      * @return The decoded bitmap, or null if the image could not be decoded.
649      */
decodeByteArray(byte[] data, int offset, int length)650     public static Bitmap decodeByteArray(byte[] data, int offset, int length) {
651         return decodeByteArray(data, offset, length, null);
652     }
653 
654     /**
655      * Set the newly decoded bitmap's density based on the Options.
656      */
setDensityFromOptions(Bitmap outputBitmap, Options opts)657     private static void setDensityFromOptions(Bitmap outputBitmap, Options opts) {
658         if (outputBitmap == null || opts == null) return;
659 
660         final int density = opts.inDensity;
661         if (density != 0) {
662             outputBitmap.setDensity(density);
663             final int targetDensity = opts.inTargetDensity;
664             if (targetDensity == 0 || density == targetDensity || density == opts.inScreenDensity) {
665                 return;
666             }
667 
668             byte[] np = outputBitmap.getNinePatchChunk();
669             final boolean isNinePatch = np != null && NinePatch.isNinePatchChunk(np);
670             if (opts.inScaled || isNinePatch) {
671                 outputBitmap.setDensity(targetDensity);
672             }
673         } else if (opts.inBitmap != null) {
674             // bitmap was reused, ensure density is reset
675             outputBitmap.setDensity(Bitmap.getDefaultDensity());
676         }
677     }
678 
679     /**
680      * Decode an input stream into a bitmap. If the input stream is null, or
681      * cannot be used to decode a bitmap, the function returns null.
682      * The stream's position will be where ever it was after the encoded data
683      * was read.
684      *
685      * @param is The input stream that holds the raw data to be decoded into a
686      *           bitmap.
687      * @param outPadding If not null, return the padding rect for the bitmap if
688      *                   it exists, otherwise set padding to [-1,-1,-1,-1]. If
689      *                   no bitmap is returned (null) then padding is
690      *                   unchanged.
691      * @param opts null-ok; Options that control downsampling and whether the
692      *             image should be completely decoded, or just is size returned.
693      * @return The decoded bitmap, or null if the image data could not be
694      *         decoded, or, if opts is non-null, if opts requested only the
695      *         size be returned (in opts.outWidth and opts.outHeight)
696      * @throws IllegalArgumentException if {@link BitmapFactory.Options#inPreferredConfig}
697      *         is {@link android.graphics.Bitmap.Config#HARDWARE}
698      *         and {@link BitmapFactory.Options#inMutable} is set, if the specified color space
699      *         is not {@link ColorSpace.Model#RGB RGB}, or if the specified color space's transfer
700      *         function is not an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}
701      *
702      * <p class="note">Prior to {@link android.os.Build.VERSION_CODES#KITKAT},
703      * if {@link InputStream#markSupported is.markSupported()} returns true,
704      * <code>is.mark(1024)</code> would be called. As of
705      * {@link android.os.Build.VERSION_CODES#KITKAT}, this is no longer the case.</p>
706      */
decodeStream(InputStream is, Rect outPadding, Options opts)707     public static Bitmap decodeStream(InputStream is, Rect outPadding, Options opts) {
708         // we don't throw in this case, thus allowing the caller to only check
709         // the cache, and not force the image to be decoded.
710         if (is == null) {
711             return null;
712         }
713         validate(opts);
714 
715         Bitmap bm = null;
716 
717         Trace.traceBegin(Trace.TRACE_TAG_GRAPHICS, "decodeBitmap");
718         try {
719             if (is instanceof AssetManager.AssetInputStream) {
720                 final long asset = ((AssetManager.AssetInputStream) is).getNativeAsset();
721                 bm = nativeDecodeAsset(asset, outPadding, opts);
722             } else {
723                 bm = decodeStreamInternal(is, outPadding, opts);
724             }
725 
726             if (bm == null && opts != null && opts.inBitmap != null) {
727                 throw new IllegalArgumentException("Problem decoding into existing bitmap");
728             }
729 
730             setDensityFromOptions(bm, opts);
731         } finally {
732             Trace.traceEnd(Trace.TRACE_TAG_GRAPHICS);
733         }
734 
735         return bm;
736     }
737 
738     /**
739      * Private helper function for decoding an InputStream natively. Buffers the input enough to
740      * do a rewind as needed, and supplies temporary storage if necessary. is MUST NOT be null.
741      */
decodeStreamInternal(InputStream is, Rect outPadding, Options opts)742     private static Bitmap decodeStreamInternal(InputStream is, Rect outPadding, Options opts) {
743         // ASSERT(is != null);
744         byte [] tempStorage = null;
745         if (opts != null) tempStorage = opts.inTempStorage;
746         if (tempStorage == null) tempStorage = new byte[DECODE_BUFFER_SIZE];
747         return nativeDecodeStream(is, tempStorage, outPadding, opts);
748     }
749 
750     /**
751      * Decode an input stream into a bitmap. If the input stream is null, or
752      * cannot be used to decode a bitmap, the function returns null.
753      * The stream's position will be where ever it was after the encoded data
754      * was read.
755      *
756      * @param is The input stream that holds the raw data to be decoded into a
757      *           bitmap.
758      * @return The decoded bitmap, or null if the image data could not be decoded.
759      */
decodeStream(InputStream is)760     public static Bitmap decodeStream(InputStream is) {
761         return decodeStream(is, null, null);
762     }
763 
764     /**
765      * Decode a bitmap from the file descriptor. If the bitmap cannot be decoded
766      * return null. The position within the descriptor will not be changed when
767      * this returns, so the descriptor can be used again as-is.
768      *
769      * @param fd The file descriptor containing the bitmap data to decode
770      * @param outPadding If not null, return the padding rect for the bitmap if
771      *                   it exists, otherwise set padding to [-1,-1,-1,-1]. If
772      *                   no bitmap is returned (null) then padding is
773      *                   unchanged.
774      * @param opts null-ok; Options that control downsampling and whether the
775      *             image should be completely decoded, or just its size returned.
776      * @return the decoded bitmap, or null
777      * @throws IllegalArgumentException if {@link BitmapFactory.Options#inPreferredConfig}
778      *         is {@link android.graphics.Bitmap.Config#HARDWARE}
779      *         and {@link BitmapFactory.Options#inMutable} is set, if the specified color space
780      *         is not {@link ColorSpace.Model#RGB RGB}, or if the specified color space's transfer
781      *         function is not an {@link ColorSpace.Rgb.TransferParameters ICC parametric curve}
782      */
decodeFileDescriptor(FileDescriptor fd, Rect outPadding, Options opts)783     public static Bitmap decodeFileDescriptor(FileDescriptor fd, Rect outPadding, Options opts) {
784         validate(opts);
785         Bitmap bm;
786 
787         Trace.traceBegin(Trace.TRACE_TAG_GRAPHICS, "decodeFileDescriptor");
788         try {
789             if (nativeIsSeekable(fd)) {
790                 bm = nativeDecodeFileDescriptor(fd, outPadding, opts);
791             } else {
792                 FileInputStream fis = new FileInputStream(fd);
793                 try {
794                     bm = decodeStreamInternal(fis, outPadding, opts);
795                 } finally {
796                     try {
797                         fis.close();
798                     } catch (Throwable t) {/* ignore */}
799                 }
800             }
801 
802             if (bm == null && opts != null && opts.inBitmap != null) {
803                 throw new IllegalArgumentException("Problem decoding into existing bitmap");
804             }
805 
806             setDensityFromOptions(bm, opts);
807         } finally {
808             Trace.traceEnd(Trace.TRACE_TAG_GRAPHICS);
809         }
810         return bm;
811     }
812 
813     /**
814      * Decode a bitmap from the file descriptor. If the bitmap cannot be decoded
815      * return null. The position within the descriptor will not be changed when
816      * this returns, so the descriptor can be used again as is.
817      *
818      * @param fd The file descriptor containing the bitmap data to decode
819      * @return the decoded bitmap, or null
820      */
decodeFileDescriptor(FileDescriptor fd)821     public static Bitmap decodeFileDescriptor(FileDescriptor fd) {
822         return decodeFileDescriptor(fd, null, null);
823     }
824 
nativeDecodeStream(InputStream is, byte[] storage, Rect padding, Options opts)825     private static native Bitmap nativeDecodeStream(InputStream is, byte[] storage,
826             Rect padding, Options opts);
nativeDecodeFileDescriptor(FileDescriptor fd, Rect padding, Options opts)827     private static native Bitmap nativeDecodeFileDescriptor(FileDescriptor fd,
828             Rect padding, Options opts);
nativeDecodeAsset(long nativeAsset, Rect padding, Options opts)829     private static native Bitmap nativeDecodeAsset(long nativeAsset, Rect padding, Options opts);
nativeDecodeByteArray(byte[] data, int offset, int length, Options opts)830     private static native Bitmap nativeDecodeByteArray(byte[] data, int offset,
831             int length, Options opts);
nativeIsSeekable(FileDescriptor fd)832     private static native boolean nativeIsSeekable(FileDescriptor fd);
833 }
834