Mosaic.java revision b28b9c0fa991bc97e8aa11da83d27f71fdfef6da
1/* 2 * Copyright (C) 2011 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 17package com.android.camera.panorama; 18 19/** 20 * The Java interface to JNI calls regarding mosaic stitching. 21 * 22 * A high-level usage is: 23 * 24 * Mosaic mosaic = new Mosaic(); 25 * mosaic.setSourceImageDimensions(width, height); 26 * mosaic.reset(blendType); 27 * 28 * while ((pixels = hasNextImage()) != null) { 29 * mosaic.setSourceImage(pixels); 30 * } 31 * 32 * mosaic.createMosaic(highRes); 33 * byte[] result = mosaic.getFinalMosaic(); 34 * 35 */ 36public class Mosaic { 37 /** 38 * In this mode, the images are stitched together in the same spatial arrangement as acquired 39 * i.e. if the user follows a curvy trajectory, the image boundary of the resulting mosaic will 40 * be curved in the same manner. This mode is useful if the user wants to capture a mosaic as 41 * if "painting" the scene using the smart-phone device and does not want any corrective warps 42 * to distort the captured images. 43 */ 44 public static final int BLENDTYPE_FULL = 0; 45 46 /** 47 * This mode is the same as BLENDTYPE_FULL except that the resulting mosaic is rotated 48 * to balance the first and last images to be approximately at the same vertical offset in the 49 * output mosaic. This is useful when acquiring a mosaic by a typical panning-like motion to 50 * remove a one-sided curve in the mosaic (typically due to the camera not staying horizontal 51 * during the video capture) and convert it to a more symmetrical "smiley-face" like output. 52 */ 53 public static final int BLENDTYPE_PAN = 1; 54 55 /** 56 * This mode compensates for typical "smiley-face" like output in longer mosaics and creates 57 * a rectangular mosaic with minimal black borders (by unwrapping the mosaic onto an imaginary 58 * cylinder). If the user follows a curved trajectory (instead of a perfect panning trajectory), 59 * the resulting mosaic here may suffer from some image distortions in trying to map the 60 * trajectory to a cylinder. 61 */ 62 public static final int BLENDTYPE_CYLINDERPAN = 2; 63 64 /** 65 * This mode is basically BLENDTYPE_CYLINDERPAN plus doing a rectangle cropping before returning 66 * the mosaic. The mode is useful for making the resulting mosaic have a rectangle shape. 67 */ 68 public static final int BLENDTYPE_HORIZONTAL =3; 69 70 /** 71 * This strip type will use the default thin strips where the strips are 72 * spaced according to the image capture rate. 73 */ 74 public static final int STRIPTYPE_THIN = 0; 75 76 /** 77 * This strip type will use wider strips for blending. The strip separation 78 * is controlled by a threshold on the native side. Since the strips are 79 * wider, there is an additional cross-fade blending step to make the seam 80 * boundaries smoother. Since this mode uses lesser image frames, it is 81 * computationally more efficient than the thin strip mode. 82 */ 83 public static final int STRIPTYPE_WIDE = 1; 84 85 /** 86 * Return flags returned by createMosaic() are one of the following. 87 */ 88 public static final int MOSAIC_RET_OK = 1; 89 public static final int MOSAIC_RET_ERROR = -1; 90 public static final int MOSAIC_RET_CANCELLED = -2; 91 92 static { 93 System.loadLibrary("jni_mosaic"); 94 } 95 96 /** 97 * Allocate memory for the image frames at the given resolution. 98 * 99 * @param width width of the input frames in pixels 100 * @param height height of the input frames in pixels 101 */ 102 public native void allocateMosaicMemory(int width, int height); 103 104 /** 105 * Free memory allocated by allocateMosaicMemory. 106 * 107 */ 108 public native void freeMosaicMemory(); 109 110 /** 111 * Pass the input image frame to the native layer. Each time the a new 112 * source image t is set, the transformation matrix from the first source 113 * image to t is computed and returned. 114 * 115 * @param pixels source image of NV21 format. 116 * @return Float array of length 10; first 9 entries correspond to the 3x3 117 * transformation matrix between the first frame and the passed frame, 118 * and the last entry is the number of the passed frame, 119 * where the counting starts from 1. 120 */ 121 public native float[] setSourceImage(byte[] pixels); 122 123 /** 124 * This is an alternative to the setSourceImage function above. This should 125 * be called when the image data is already on the native side in a fixed 126 * byte array. In implementation, this array is filled by the GL thread 127 * using glReadPixels directly from GPU memory (where it is accessed by 128 * an associated SurfaceTexture). 129 * 130 * @return Float array of length 10; first 9 entries correspond to the 3x3 131 * transformation matrix between the first frame and the passed frame, 132 * and the last entry is the number of the passed frame, 133 * where the counting starts from 1. 134 */ 135 public native float[] setSourceImageFromGPU(); 136 137 /** 138 * Set the type of blending. 139 * 140 * @param type the blending type defined in the class. {BLENDTYPE_FULL, 141 * BLENDTYPE_PAN, BLENDTYPE_CYLINDERPAN, BLENDTYPE_HORIZONTAL} 142 */ 143 public native void setBlendingType(int type); 144 145 /** 146 * Set the type of strips to use for blending. 147 * @param type the blending strip type to use {STRIPTYPE_THIN, 148 * STRIPTYPE_WIDE}. 149 */ 150 public native void setStripType(int type); 151 152 /** 153 * Tell the native layer to create the final mosaic after all the input frame 154 * data have been collected. 155 * The case of generating high-resolution mosaic may take dozens of seconds to finish. 156 * 157 * @param value True means generating a high-resolution mosaic - 158 * which is based on the original images set in setSourceImage(). 159 * False means generating a low-resolution version - 160 * which is based on 1/4 downscaled images from the original images. 161 * @return Returns a status code suggesting if the mosaic building was 162 * successful, in error, or was cancelled by the user. 163 */ 164 public native int createMosaic(boolean value); 165 166 /** 167 * Get the data for the created mosaic. 168 * 169 * @return Returns an integer array which contains the final mosaic in the ARGB_8888 format. 170 * The first MosaicWidth*MosaicHeight values contain the image data, followed by 2 171 * integers corresponding to the values MosaicWidth and MosaicHeight respectively. 172 */ 173 public native int[] getFinalMosaic(); 174 175 /** 176 * Get the data for the created mosaic. 177 * 178 * @return Returns a byte array which contains the final mosaic in the NV21 format. 179 * The first MosaicWidth*MosaicHeight*1.5 values contain the image data, followed by 180 * 8 bytes which pack the MosaicWidth and MosaicHeight integers into 4 bytes each 181 * respectively. 182 */ 183 public native byte[] getFinalMosaicNV21(); 184 185 /** 186 * Reset the state of the frame arrays which maintain the captured frame data. 187 * Also re-initializes the native mosaic object to make it ready for capturing a new mosaic. 188 */ 189 public native void reset(); 190 191 /** 192 * Get the progress status of the mosaic computation process. 193 * @param hires Boolean flag to select whether to report progress of the 194 * low-res or high-res mosaicer. 195 * @param cancelComputation Boolean flag to allow cancelling the 196 * mosaic computation when needed from the GUI end. 197 * @return Returns a number from 0-100 where 50 denotes that the mosaic 198 * computation is 50% done. 199 */ 200 public native int reportProgress(boolean hires, boolean cancelComputation); 201} 202