platform-abstractions/portable/image-operations.h

   1 /*
   2  * Copyright (c) 2017 Samsung Electronics Co., Ltd.
   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
  18 #ifndef DALI_INTERNAL_PLATFORM_IMAGE_OPERATIONS_H_
  19 #define DALI_INTERNAL_PLATFORM_IMAGE_OPERATIONS_H_
  20
  21 // EXTERNAL INCLUDES
  22 #include <stdint.h>
  23
  24 // INTERNAL INCLUDES
  25 #include <dali/integration-api/bitmap.h>
  26 #include <dali/public-api/images/image-operations.h>
  27
  28 namespace Dali
  29 {
  30 namespace Internal
  31 {
  32 namespace Platform
  33 {
  34
  35 /**
  36  * @brief Identify which combination of x and y dimensions matter in terminating iterative box filtering.
  37  */
  38 enum BoxDimensionTest
  39 {
  40   BoxDimensionTestEither,
  41   BoxDimensionTestBoth,
  42   BoxDimensionTestX,
  43   BoxDimensionTestY
  44 };
  45
  46 /**
  47  * @brief The integer dimensions of an image or a region of an image packed into
  48  *        16 bits per component.
  49  * @note  This can only be used for images of up to 65535 x 65535 pixels.
  50   */
  51 typedef Uint16Pair ImageDimensions;
  52
  53 /**
  54  * @brief Work out the true desired width and height, accounting for special
  55  * rules for zeros in either or both input requested dimensions.
  56  *
  57  * @param[in] rawDimensions Width and height of image before processing.
  58  * @param[in] requestedDimensions Width and height of area to scale image into. Can be zero.
  59  * @return Dimensions of area to scale image into after special rules are applied.
  60  */
  61 ImageDimensions CalculateDesiredDimensions( ImageDimensions rawDimensions, ImageDimensions requestedDimensions );
  62
  63 /**
  64  * @defgroup BitmapOperations Bitmap-to-Bitmap Image operations.
  65  * @{
  66  */
  67
  68 /**
  69  * @brief Apply requested attributes to bitmap.
  70  *
  71  * This is the top-level function which runs the on-load image post-processing
  72  * pipeline. Bitmaps enter here as loaded from the file system by the file
  73  * loaders and leave downscaled and filtered as requested by the application,
  74  * ready for use.
  75  *
  76  * @param[in] bitmap The input bitmap.
  77  * @param[in] requestedAttributes Attributes which should be applied to bitmap.
  78  * @return A bitmap which results from applying the requested attributes to the
  79  *         bitmap passed-in, or the original bitmap passed in if the attributes
  80  *         have no effect.
  81  */
  82 Integration::BitmapPtr ApplyAttributesToBitmap( Integration::BitmapPtr bitmap, ImageDimensions dimensions, FittingMode::Type fittingMode = FittingMode::DEFAULT, SamplingMode::Type samplingMode = SamplingMode::DEFAULT );
  83
  84 /**
  85  * @brief Apply downscaling to a bitmap according to requested attributes.
  86  * @note The input bitmap pixel buffer may be modified and used as scratch working space for efficiency, so it must be discarded.
  87  **/
  88 Integration::BitmapPtr DownscaleBitmap( Integration::Bitmap& bitmap, ImageDimensions desired, FittingMode::Type fittingMode, SamplingMode::Type samplingMode );
  89 /**@}*/
  90
  91 /**
  92  * @defgroup ImageBufferScalingAlgorithms Pixel buffer-level scaling algorithms.
  93  * @{
  94  */
  95
  96 /**
  97  * @brief Destructive in-place downscaling by a power of 2 factor.
  98  *
  99  * A box filter with a 2x2 kernel is repeatedly applied as long as the result
 100  * of the next downscaling step would not be smaller than the desired
 101  * dimensions.
 102  * @param[in,out] pixels The buffer both to read from and write the result to.
 103  * @param[in]     pixelFormat The format of the image pointed at by pixels.
 104  * @param[in]     inputWidth The width of the input image.
 105  * @param[in]     inputHeight The height of the input image.
 106  * @param[in]     desiredWidth The width the client is requesting.
 107  * @param[in]     desiredHeight The height the client is requesting.
 108  * @param[out]    outWidth  The resulting width after downscaling.
 109  * @param[out]    outHeight The resulting height after downscaling.
 110  */
 111 void DownscaleInPlacePow2( unsigned char * const pixels,
 112                            Pixel::Format pixelFormat,
 113                            unsigned int inputWidth,
 114                            unsigned int inputHeight,
 115                            unsigned int desiredWidth,
 116                            unsigned int desiredHeight,
 117                            FittingMode::Type fittingMode,
 118                            SamplingMode::Type samplingMode,
 119                            unsigned& outWidth,
 120                            unsigned& outHeight );
 121
 122 /**
 123  * @brief Destructive in-place downscaling by a power of 2 factor.
 124  *
 125  * A box filter with a 2x2 kernel is repeatedly applied as long as the result
 126  * of the next downscaling step would not be smaller than the desired
 127  * dimensions.
 128  * @param[in,out] pixels The buffer both to read from and write the result to.
 129  * @param[in]     inputWidth The width of the input image.
 130  * @param[in]     inputHeight The height of the input image.
 131  * @param[in]     desiredWidth The width the client is requesting.
 132  * @param[in]     desiredHeight The height the client is requesting.
 133  * @param[out]    outWidth  The resulting width after downscaling.
 134  * @param[out]    outHeight The resulting height after downscaling.
 135  */
 136 void DownscaleInPlacePow2RGB888( unsigned char * pixels,
 137                                  unsigned int inputWidth,
 138                                  unsigned int inputHeight,
 139                                  unsigned int desiredWidth,
 140                                  unsigned int desiredHeight,
 141                                  BoxDimensionTest dimensionTest,
 142                                  unsigned int& outWidth,
 143                                  unsigned int& outHeight );
 144
 145 /**
 146  * @copydoc DownscaleInPlacePow2RGB888
 147  */
 148 void DownscaleInPlacePow2RGBA8888( unsigned char * pixels,
 149                                    unsigned int inputWidth,
 150                                    unsigned int inputHeight,
 151                                    unsigned int desiredWidth,
 152                                    unsigned int desiredHeight,
 153                                    BoxDimensionTest dimensionTest,
 154                                    unsigned int& outWidth,
 155                                    unsigned int& outHeight );
 156
 157 /**
 158  * @copydoc DownscaleInPlacePow2RGB888
 159  *
 160  * For the 2-byte packed 16 bit format RGB565.
 161  */
 162 void DownscaleInPlacePow2RGB565( unsigned char * pixels,
 163                                  unsigned int inputWidth,
 164                                  unsigned int inputHeight,
 165                                  unsigned int desiredWidth,
 166                                  unsigned int desiredHeight,
 167                                  BoxDimensionTest dimensionTest,
 168                                  unsigned int& outWidth,
 169                                  unsigned int& outHeight );
 170
 171 /**
 172  * @copydoc DownscaleInPlacePow2RGB888
 173  *
 174  * For 2-byte formats such as lum8alpha8, but not packed 16 bit formats like RGB565.
 175  */
 176 void DownscaleInPlacePow2ComponentPair( unsigned char * pixels,
 177                                         unsigned int inputWidth,
 178                                         unsigned int inputHeight,
 179                                         unsigned int desiredWidth,
 180                                         unsigned int desiredHeight,
 181                                         BoxDimensionTest dimensionTest,
 182                                         unsigned int& outWidth,
 183                                         unsigned int& outHeight );
 184
 185 /**
 186  * @copydoc DownscaleInPlacePow2RGB888
 187  *
 188  * For single-byte formats such as lum8 or alpha8.
 189  */
 190 void DownscaleInPlacePow2SingleBytePerPixel( unsigned char * pixels,
 191                                              unsigned int inputWidth,
 192                                              unsigned int inputHeight,
 193                                              unsigned int desiredWidth,
 194                                              unsigned int desiredHeight,
 195                                              BoxDimensionTest dimensionTest,
 196                                              unsigned int& outWidth,
 197                                              unsigned int& outHeight );
 198
 199 /**
 200  * @brief Rescales an input image into the exact output dimensions passed-in.
 201  *
 202  * Uses point sampling, equivalent to GL_NEAREST texture filter mode, for the
 203  * fastest results, at the expense of aliasing (noisy images) when downscaling.
 204  * @note inPixels is allowed to alias outPixels if this is a downscaling,
 205  * but not for upscaling.
 206  */
 207 void PointSample( const unsigned char * inPixels,
 208                   unsigned int inputWidth,
 209                   unsigned int inputHeight,
 210                   Pixel::Format pixelFormat,
 211                   unsigned char * outPixels,
 212                   unsigned int desiredWidth,
 213                   unsigned int desiredHeight );
 214
 215 /**
 216  * @copydoc PointSample
 217  *
 218  * Specialised for 4-byte formats like RGBA8888 and BGRA8888.
 219  */
 220 void PointSample4BPP( const unsigned char * inPixels,
 221                       unsigned int inputWidth,
 222                       unsigned int inputHeight,
 223                       unsigned char * outPixels,
 224                       unsigned int desiredWidth,
 225                       unsigned int desiredHeight );
 226
 227 /**
 228  * @copydoc PointSample
 229  *
 230  * Specialised for 3-byte formats like RGB888 and BGR888.
 231  */
 232 void PointSample3BPP( const unsigned char * inPixels,
 233                       unsigned int inputWidth,
 234                       unsigned int inputHeight,
 235                       unsigned char * outPixels,
 236                       unsigned int desiredWidth,
 237                       unsigned int desiredHeight );
 238
 239 /**
 240  * @copydoc PointSample
 241  *
 242  * Specialised for 2-byte formats like LA88.
 243  */
 244 void PointSample2BPP( const unsigned char * inPixels,
 245                       unsigned int inputWidth,
 246                       unsigned int inputHeight,
 247                       unsigned char * outPixels,
 248                       unsigned int desiredWidth,
 249                       unsigned int desiredHeight );
 250
 251 /**
 252  * @copydoc PointSample
 253  *
 254  * Specialised for 1-byte formats like L8 and A8.
 255  */
 256 void PointSample1BPP( const unsigned char * inPixels,
 257                       unsigned int inputWidth,
 258                       unsigned int inputHeight,
 259                       unsigned char * outPixels,
 260                       unsigned int desiredWidth,
 261                       unsigned int desiredHeight );
 262
 263 /**
 264  * @brief Resample input image to output image using a bilinear filter.
 265  *
 266  * Each output pixel is formed of a weighted sum of a 2x2 block of four input
 267  * pixels
 268  * @pre inPixels must not alias outPixels. The input image should be a totally
 269  * separate buffer from the input one.
 270  */
 271 void LinearSample( const unsigned char * __restrict__ inPixels,
 272                    ImageDimensions inDimensions,
 273                    Pixel::Format pixelFormat,
 274                    unsigned char * __restrict__ outPixels,
 275                    ImageDimensions outDimensions );
 276
 277 /**
 278  * @copydoc LinearSample
 279  *
 280  * Specialised for one byte per pixel formats.
 281  */
 282 void LinearSample1BPP( const unsigned char * __restrict__ inPixels,
 283                        ImageDimensions inputDimensions,
 284                        unsigned char * __restrict__ outPixels,
 285                        ImageDimensions desiredDimensions );
 286
 287 /**
 288  * @copydoc LinearSample
 289  *
 290  * Specialised for two byte per pixel formats.
 291  */
 292 void LinearSample2BPP( const unsigned char * __restrict__ inPixels,
 293                        ImageDimensions inputDimensions,
 294                        unsigned char * __restrict__ outPixels,
 295                        ImageDimensions desiredDimensions );
 296
 297 /**
 298  * @copydoc LinearSample
 299  *
 300  * Specialised for RGB565 16 bit pixel format.
 301  */
 302 void LinearSampleRGB565( const unsigned char * __restrict__ inPixels,
 303                        ImageDimensions inputDimensions,
 304                        unsigned char * __restrict__ outPixels,
 305                        ImageDimensions desiredDimensions );
 306
 307 /**
 308  * @copydoc LinearSample
 309  *
 310  * Specialised for three byte per pixel formats like RGB888.
 311  */
 312 void LinearSample3BPP( const unsigned char * __restrict__ inPixels,
 313                        ImageDimensions inputDimensions,
 314                        unsigned char * __restrict__ outPixels,
 315                        ImageDimensions desiredDimensions );
 316
 317 /**
 318  * @copydoc LinearSample
 319  *
 320  * Specialised for four byte per pixel formats like RGBA8888.
 321  * @note, If used on RGBA8888, the A component will be blended independently.
 322  */
 323 void LinearSample4BPP( const unsigned char * __restrict__ inPixels,
 324                        ImageDimensions inputDimensions,
 325                        unsigned char * __restrict__ outPixels,
 326                        ImageDimensions desiredDimensions );
 327
 328 /**
 329  * @brief Resamples the input image with the Lanczos algorithm.
 330  *
 331  * @pre @p inPixels must not alias @p outPixels. The input image should be a totally
 332  * separate buffer from the output buffer.
 333  *
 334  * @param[in] inPixels Pointer to the input image buffer.
 335  * @param[in] inputDimensions The input dimensions of the image.
 336  * @param[out] outPixels Pointer to the output image buffer.
 337  * @param[in] desiredDimensions The output dimensions of the image.
 338  */
 339 void LanczosSample4BPP( const unsigned char * __restrict__ inPixels,
 340                         ImageDimensions inputDimensions,
 341                         unsigned char * __restrict__ outPixels,
 342                         ImageDimensions desiredDimensions );
 343
 344 /**
 345  * @brief Resamples the input image with the Lanczos algorithm.
 346  *
 347  * @pre @p inPixels must not alias @p outPixels. The input image should be a totally
 348  * separate buffer from the output buffer.
 349  *
 350  * @param[in] inPixels Pointer to the input image buffer.
 351  * @param[in] inputDimensions The input dimensions of the image.
 352  * @param[out] outPixels Pointer to the output image buffer.
 353  * @param[in] desiredDimensions The output dimensions of the image.
 354  */
 355 void LanczosSample1BPP( const unsigned char * __restrict__ inPixels,
 356                         ImageDimensions inputDimensions,
 357                         unsigned char * __restrict__ outPixels,
 358                         ImageDimensions desiredDimensions );
 359
 360 /**@}*/
 361
 362 /**
 363  * @defgroup ScalingAlgorithmFragments Composable subunits of the scaling algorithms.
 364  * @{
 365  */
 366
 367 /**
 368  * @brief Average adjacent pairs of pixels, overwriting the input array.
 369  * @param[in,out] pixels The array of pixels to work on.
 370  * @param[i]      width  The number of pixels in the array passed-in.
 371  */
 372 void HalveScanlineInPlaceRGB888( unsigned char * pixels, unsigned int width );
 373
 374 /**
 375  * @copydoc HalveScanlineInPlaceRGB888
 376  */
 377 void HalveScanlineInPlaceRGBA8888( unsigned char * pixels, unsigned int width );
 378
 379 /**
 380  * @copydoc HalveScanlineInPlaceRGB888
 381  */
 382 void HalveScanlineInPlaceRGB565( unsigned char * pixels, unsigned int width );
 383
 384 /**
 385  * @copydoc HalveScanlineInPlaceRGB888
 386  */
 387 void HalveScanlineInPlace2Bytes( unsigned char * pixels, unsigned int width );
 388
 389 /**
 390  * @copydoc HalveScanlineInPlaceRGB888
 391  */
 392 void HalveScanlineInPlace1Byte( unsigned char * pixels, unsigned int width );
 393
 394 /**
 395  * @brief Average pixels at corresponding offsets in two scanlines.
 396  *
 397  * outputScanline is allowed to alias scanline1.
 398  * @param[in] scanline1 First scanline of pixels to average.
 399  * @param[in] scanline2 Second scanline of pixels to average.
 400  * @param[out] outputScanline Destination for the averaged pixels.
 401  * @param[in] width The widths of all the scanlines passed-in.
 402  */
 403 void AverageScanlines1( const unsigned char * scanline1,
 404                         const unsigned char * scanline2,
 405                         unsigned char* outputScanline,
 406                         /** Image width in pixels (1 byte == 1 pixel: e.g. lum8 or alpha8).*/
 407                         unsigned int width );
 408
 409 /**
 410  * @copydoc AverageScanlines1
 411  */
 412 void AverageScanlines2( const unsigned char * scanline1,
 413                         const unsigned char * scanline2,
 414                         unsigned char* outputScanline,
 415                         /** Image width in pixels (2 bytes == 1 pixel: e.g. lum8alpha8).*/
 416                         unsigned int width );
 417
 418 /**
 419  * @copydoc AverageScanlines1
 420  */
 421 void AverageScanlines3( const unsigned char * scanline1,
 422                         const unsigned char * scanline2,
 423                         unsigned char* outputScanline,
 424                         /** Image width in pixels (3 bytes == 1 pixel: e.g. RGB888).*/
 425                         unsigned int width );
 426
 427 /**
 428  * @copydoc AverageScanlines1
 429  */
 430 void AverageScanlinesRGBA8888( const unsigned char * scanline1,
 431                                const unsigned char * scanline2,
 432                                unsigned char * outputScanline,
 433                                unsigned int width );
 434
 435 /**
 436  * @copydoc AverageScanlines1
 437  */
 438 void AverageScanlinesRGB565( const unsigned char * scanline1,
 439                              const unsigned char * scanline2,
 440                              unsigned char* outputScanline,
 441                              unsigned int width );
 442 /**@}*/
 443
 444 /**
 445  * @defgroup TestableInlines Inline functions exposed in header to allow unit testing.
 446  * @{
 447  */
 448
 449 /**
 450  * @brief Average two integer arguments.
 451  * @return The average of two uint arguments.
 452  * @param[in] a First component to average.
 453  * @param[in] b Second component to average.
 454  **/
 455 inline unsigned int AverageComponent( unsigned int a, unsigned int b )
 456 {
 457   unsigned int avg = (a + b) >> 1u;
 458   return avg;
 459 }
 460
 461 /**
 462  * @brief Average a pair of RGBA8888 pixels.
 463  * @return The average of two RGBA8888 pixels.
 464  * @param[in] a First pixel to average.
 465  * @param[in] b Second pixel to average
 466  **/
 467 inline uint32_t AveragePixelRGBA8888( uint32_t a, uint32_t b )
 468 {
 469   const unsigned int avg =
 470     ((AverageComponent( (a & 0xff000000) >> 1u, (b & 0xff000000) >> 1u ) << 1u) & 0xff000000 ) +
 471     (AverageComponent( a & 0x00ff0000, b & 0x00ff0000 ) & 0x00ff0000 ) +
 472     (AverageComponent( a & 0x0000ff00, b & 0x0000ff00 ) & 0x0000ff00 ) +
 473     (AverageComponent( a & 0x000000ff, b & 0x000000ff ) );
 474   return avg;
 475   ///@ToDo: Optimise by trying return (((a ^ b) & 0xfefefefeUL) >> 1) + (a & b);
 476   ///@ToDo: Optimise for ARM using the single ARMV6 instruction: UHADD8  R4, R0, R5. This is not Neon. It runs in the normal integer pipeline so there is no downside like a stall moving between integer and copro.
 477 }
 478
 479 /**
 480  * @brief Average a pair of RGB565 pixels.
 481  * @param a[in] Low 16 bits hold a color value as RGB565 to average with parameter b.
 482  * @param b[in] Low 16 bits hold a color value as RGB565 to average with parameter a.
 483  * @return The average color of the two RGB565 pixels passed in, in the low 16 bits of the returned value.
 484  **/
 485 inline uint32_t AveragePixelRGB565( uint32_t a, uint32_t b )
 486 {
 487   const unsigned int avg =
 488     (AverageComponent( a & 0xf800, b & 0xf800 ) & 0xf800 ) +
 489     (AverageComponent( a & 0x7e0,  b & 0x7e0 )  & 0x7e0 ) +
 490     (AverageComponent( a & 0x1f,   b & 0x1f ) );
 491   return avg;
 492 }
 493
 494 /** @return The weighted blend of two integers as a 16.16 fixed-point number, given a 0.16 fixed-point blending factor. */
 495 inline unsigned int WeightedBlendIntToFixed1616(unsigned int a, unsigned int b, unsigned int fractBlend )
 496 {
 497   DALI_ASSERT_DEBUG( fractBlend <= 65535u && "Factor should be in 0.16 fixed-point." );
 498   const unsigned int weightedAFixed = a * (65535u - fractBlend);
 499   const unsigned int weightedBFixed = b * fractBlend;
 500   const unsigned blended = (weightedAFixed + weightedBFixed);
 501   return blended;
 502 }
 503
 504 /** @brief Blend two 16.16 inputs to give a 16.32 output. */
 505 inline uint64_t WeightedBlendFixed1616ToFixed1632(unsigned int a, unsigned int b, unsigned int fractBlend )
 506 {
 507   DALI_ASSERT_DEBUG( fractBlend <= 65535u && "Factor should be in 0.16 fixed-point." );
 508   // Blend while promoting intermediates to 16.32 fixed point:
 509   const uint64_t weightedAFixed = uint64_t(a) * (65535u - fractBlend);
 510   const uint64_t weightedBFixed = uint64_t(b) * fractBlend;
 511   const uint64_t blended = (weightedAFixed + weightedBFixed);
 512   return blended;
 513 }
 514
 515 /**
 516  * @brief Blend 4 taps into one value using horizontal and vertical weights.
 517  */
 518 inline unsigned int BilinearFilter1Component(unsigned int tl, unsigned int tr, unsigned int bl, unsigned int br, unsigned int fractBlendHorizontal, unsigned int fractBlendVertical )
 519 {
 520   DALI_ASSERT_DEBUG( fractBlendHorizontal <= 65535u && "Factor should be in 0.16 fixed-point." );
 521   DALI_ASSERT_DEBUG( fractBlendVertical   <= 65535u && "Factor should be in 0.16 fixed-point." );
 522
 523   const unsigned int topBlend = WeightedBlendIntToFixed1616( tl, tr, fractBlendHorizontal );
 524   const unsigned int botBlend = WeightedBlendIntToFixed1616( bl, br, fractBlendHorizontal );
 525   const uint64_t blended2x2 = WeightedBlendFixed1616ToFixed1632( topBlend, botBlend, fractBlendVertical );
 526   const unsigned int rounded = (blended2x2 + (1u << 31u) ) >> 32u;
 527   return rounded;
 528 }
 529
 530 /**@}*/
 531
 532 } /* namespace Platform */
 533 } /* namespace Internal */
 534 } /* namespace Dali */
 535
 536 #endif /* DALI_INTERNAL_PLATFORM_IMAGE_OPERATIONS_H_ */