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 17 package com.android.camera; 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 */ 36 public 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 public static final int MOSAIC_RET_LOW_TEXTURE = -3; 92 public static final int MOSAIC_RET_FEW_INLIERS = 2; 93 94 95 static { 96 System.loadLibrary("jni_mosaic"); 97 } 98 99 /** 100 * Allocate memory for the image frames at the given resolution. 101 * 102 * @param width width of the input frames in pixels 103 * @param height height of the input frames in pixels 104 */ allocateMosaicMemory(int width, int height)105 public native void allocateMosaicMemory(int width, int height); 106 107 /** 108 * Free memory allocated by allocateMosaicMemory. 109 * 110 */ freeMosaicMemory()111 public native void freeMosaicMemory(); 112 113 /** 114 * Pass the input image frame to the native layer. Each time the a new 115 * source image t is set, the transformation matrix from the first source 116 * image to t is computed and returned. 117 * 118 * @param pixels source image of NV21 format. 119 * @return Float array of length 11; first 9 entries correspond to the 3x3 120 * transformation matrix between the first frame and the passed frame; 121 * the 10th entry is the number of the passed frame, where the counting 122 * starts from 1; and the 11th entry is the returning code, whose value 123 * is one of those MOSAIC_RET_* returning flags defined above. 124 */ setSourceImage(byte[] pixels)125 public native float[] setSourceImage(byte[] pixels); 126 127 /** 128 * This is an alternative to the setSourceImage function above. This should 129 * be called when the image data is already on the native side in a fixed 130 * byte array. In implementation, this array is filled by the GL thread 131 * using glReadPixels directly from GPU memory (where it is accessed by 132 * an associated SurfaceTexture). 133 * 134 * @return Float array of length 11; first 9 entries correspond to the 3x3 135 * transformation matrix between the first frame and the passed frame; 136 * the 10th entry is the number of the passed frame, where the counting 137 * starts from 1; and the 11th entry is the returning code, whose value 138 * is one of those MOSAIC_RET_* returning flags defined above. 139 */ setSourceImageFromGPU()140 public native float[] setSourceImageFromGPU(); 141 142 /** 143 * Set the type of blending. 144 * 145 * @param type the blending type defined in the class. {BLENDTYPE_FULL, 146 * BLENDTYPE_PAN, BLENDTYPE_CYLINDERPAN, BLENDTYPE_HORIZONTAL} 147 */ setBlendingType(int type)148 public native void setBlendingType(int type); 149 150 /** 151 * Set the type of strips to use for blending. 152 * @param type the blending strip type to use {STRIPTYPE_THIN, 153 * STRIPTYPE_WIDE}. 154 */ setStripType(int type)155 public native void setStripType(int type); 156 157 /** 158 * Tell the native layer to create the final mosaic after all the input frame 159 * data have been collected. 160 * The case of generating high-resolution mosaic may take dozens of seconds to finish. 161 * 162 * @param value True means generating a high-resolution mosaic - 163 * which is based on the original images set in setSourceImage(). 164 * False means generating a low-resolution version - 165 * which is based on 1/4 downscaled images from the original images. 166 * @return Returns a status code suggesting if the mosaic building was 167 * successful, in error, or was cancelled by the user. 168 */ createMosaic(boolean value)169 public native int createMosaic(boolean value); 170 171 /** 172 * Get the data for the created mosaic. 173 * 174 * @return Returns an integer array which contains the final mosaic in the ARGB_8888 format. 175 * The first MosaicWidth*MosaicHeight values contain the image data, followed by 2 176 * integers corresponding to the values MosaicWidth and MosaicHeight respectively. 177 */ getFinalMosaic()178 public native int[] getFinalMosaic(); 179 180 /** 181 * Get the data for the created mosaic. 182 * 183 * @return Returns a byte array which contains the final mosaic in the NV21 format. 184 * The first MosaicWidth*MosaicHeight*1.5 values contain the image data, followed by 185 * 8 bytes which pack the MosaicWidth and MosaicHeight integers into 4 bytes each 186 * respectively. 187 */ getFinalMosaicNV21()188 public native byte[] getFinalMosaicNV21(); 189 190 /** 191 * Reset the state of the frame arrays which maintain the captured frame data. 192 * Also re-initializes the native mosaic object to make it ready for capturing a new mosaic. 193 */ reset()194 public native void reset(); 195 196 /** 197 * Get the progress status of the mosaic computation process. 198 * @param hires Boolean flag to select whether to report progress of the 199 * low-res or high-res mosaicer. 200 * @param cancelComputation Boolean flag to allow cancelling the 201 * mosaic computation when needed from the GUI end. 202 * @return Returns a number from 0-100 where 50 denotes that the mosaic 203 * computation is 50% done. 204 */ reportProgress(boolean hires, boolean cancelComputation)205 public native int reportProgress(boolean hires, boolean cancelComputation); 206 } 207