| /* | 
 |  * Copyright (c) 2016, Alliance for Open Media. All rights reserved | 
 |  * | 
 |  * This source code is subject to the terms of the BSD 2 Clause License and | 
 |  * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License | 
 |  * was not distributed with this source code in the LICENSE file, you can | 
 |  * obtain it at www.aomedia.org/license/software. If the Alliance for Open | 
 |  * Media Patent License 1.0 was not distributed with this source code in the | 
 |  * PATENTS file, you can obtain it at www.aomedia.org/license/patent. | 
 |  */ | 
 |  | 
 | /**************************************************************************** | 
 |  * | 
 |  *   Module Title :     scale.c | 
 |  * | 
 |  *   Description  :     Image scaling functions. | 
 |  * | 
 |  ***************************************************************************/ | 
 |  | 
 | /**************************************************************************** | 
 | *  Header Files | 
 | ****************************************************************************/ | 
 | #include "./aom_scale_rtcd.h" | 
 | #include "aom_mem/aom_mem.h" | 
 | #include "aom_scale/aom_scale.h" | 
 | #include "aom_scale/yv12config.h" | 
 |  | 
 | typedef struct { | 
 |   int expanded_frame_width; | 
 |   int expanded_frame_height; | 
 |  | 
 |   int HScale; | 
 |   int HRatio; | 
 |   int VScale; | 
 |   int VRatio; | 
 |  | 
 |   YV12_BUFFER_CONFIG *src_yuv_config; | 
 |   YV12_BUFFER_CONFIG *dst_yuv_config; | 
 |  | 
 | } SCALE_VARS; | 
 |  | 
 | /**************************************************************************** | 
 |  * | 
 |  *  ROUTINE       : scale1d_2t1_i | 
 |  * | 
 |  *  INPUTS        : const unsigned char *source : Pointer to data to be scaled. | 
 |  *                  int source_step             : Number of pixels to step on | 
 |  *                                                in source. | 
 |  *                  unsigned int source_scale   : Scale for source (UNUSED). | 
 |  *                  unsigned int source_length  : Length of source (UNUSED). | 
 |  *                  unsigned char *dest         : Pointer to output data array. | 
 |  *                  int dest_step               : Number of pixels to step on | 
 |  *                                                in destination. | 
 |  *                  unsigned int dest_scale     : Scale for destination | 
 |  *                                                (UNUSED). | 
 |  *                  unsigned int dest_length    : Length of destination. | 
 |  * | 
 |  *  OUTPUTS       : None. | 
 |  * | 
 |  *  RETURNS       : void | 
 |  * | 
 |  *  FUNCTION      : Performs 2-to-1 interpolated scaling. | 
 |  * | 
 |  *  SPECIAL NOTES : None. | 
 |  * | 
 |  ****************************************************************************/ | 
 | static void scale1d_2t1_i(const unsigned char *source, int source_step, | 
 |                           unsigned int source_scale, unsigned int source_length, | 
 |                           unsigned char *dest, int dest_step, | 
 |                           unsigned int dest_scale, unsigned int dest_length) { | 
 |   const unsigned int source_pitch = source_step; | 
 |   const unsigned char *const dest_end = dest + dest_length * dest_step; | 
 |   (void)source_length; | 
 |   (void)source_scale; | 
 |   (void)dest_scale; | 
 |  | 
 |   source_step *= 2;  // Every other row. | 
 |  | 
 |   dest[0] = source[0];  // Special case: 1st pixel. | 
 |   source += source_step; | 
 |   dest += dest_step; | 
 |  | 
 |   while (dest < dest_end) { | 
 |     const unsigned int a = 3 * source[-source_pitch]; | 
 |     const unsigned int b = 10 * source[0]; | 
 |     const unsigned int c = 3 * source[source_pitch]; | 
 |     *dest = (unsigned char)((8 + a + b + c) >> 4); | 
 |     source += source_step; | 
 |     dest += dest_step; | 
 |   } | 
 | } | 
 |  | 
 | /**************************************************************************** | 
 |  * | 
 |  *  ROUTINE       : scale1d_2t1_ps | 
 |  * | 
 |  *  INPUTS        : const unsigned char *source : Pointer to data to be scaled. | 
 |  *                  int source_step             : Number of pixels to step on | 
 |  *                                                in source. | 
 |  *                  unsigned int source_scale   : Scale for source (UNUSED). | 
 |  *                  unsigned int source_length  : Length of source (UNUSED). | 
 |  *                  unsigned char *dest         : Pointer to output data array. | 
 |  *                  int dest_step               : Number of pixels to step on | 
 |  *                                                in destination. | 
 |  *                  unsigned int dest_scale     : Scale for destination | 
 |  *                                                (UNUSED). | 
 |  *                  unsigned int dest_length    : Length of destination. | 
 |  * | 
 |  *  OUTPUTS       : None. | 
 |  * | 
 |  *  RETURNS       : void | 
 |  * | 
 |  *  FUNCTION      : Performs 2-to-1 point subsampled scaling. | 
 |  * | 
 |  *  SPECIAL NOTES : None. | 
 |  * | 
 |  ****************************************************************************/ | 
 | static void scale1d_2t1_ps(const unsigned char *source, int source_step, | 
 |                            unsigned int source_scale, | 
 |                            unsigned int source_length, unsigned char *dest, | 
 |                            int dest_step, unsigned int dest_scale, | 
 |                            unsigned int dest_length) { | 
 |   const unsigned char *const dest_end = dest + dest_length * dest_step; | 
 |   (void)source_length; | 
 |   (void)source_scale; | 
 |   (void)dest_scale; | 
 |  | 
 |   source_step *= 2;  // Every other row. | 
 |  | 
 |   while (dest < dest_end) { | 
 |     *dest = *source; | 
 |     source += source_step; | 
 |     dest += dest_step; | 
 |   } | 
 | } | 
 | /**************************************************************************** | 
 |  * | 
 |  *  ROUTINE       : scale1d_c | 
 |  * | 
 |  *  INPUTS        : const unsigned char *source : Pointer to data to be scaled. | 
 |  *                  int source_step             : Number of pixels to step on | 
 |  *                                                in source. | 
 |  *                  unsigned int source_scale   : Scale for source. | 
 |  *                  unsigned int source_length  : Length of source (UNUSED). | 
 |  *                  unsigned char *dest         : Pointer to output data array. | 
 |  *                  int dest_step               : Number of pixels to step on | 
 |  *                                                in destination. | 
 |  *                  unsigned int dest_scale     : Scale for destination. | 
 |  *                  unsigned int dest_length    : Length of destination. | 
 |  * | 
 |  *  OUTPUTS       : None. | 
 |  * | 
 |  *  RETURNS       : void | 
 |  * | 
 |  *  FUNCTION      : Performs linear interpolation in one dimension. | 
 |  * | 
 |  *  SPECIAL NOTES : None. | 
 |  * | 
 |  ****************************************************************************/ | 
 | static void scale1d_c(const unsigned char *source, int source_step, | 
 |                       unsigned int source_scale, unsigned int source_length, | 
 |                       unsigned char *dest, int dest_step, | 
 |                       unsigned int dest_scale, unsigned int dest_length) { | 
 |   const unsigned char *const dest_end = dest + dest_length * dest_step; | 
 |   const unsigned int round_value = dest_scale / 2; | 
 |   unsigned int left_modifier = dest_scale; | 
 |   unsigned int right_modifier = 0; | 
 |   unsigned char left_pixel = source[0]; | 
 |   unsigned char right_pixel = source[source_step]; | 
 |  | 
 |   (void)source_length; | 
 |  | 
 |   /* These asserts are needed if there are boundary issues... */ | 
 |   /* assert ( dest_scale > source_scale );*/ | 
 |   /* assert ( (source_length - 1) * dest_scale >= (dest_length - 1) * | 
 |    * source_scale);*/ | 
 |  | 
 |   while (dest < dest_end) { | 
 |     *dest = (unsigned char)((left_modifier * left_pixel + | 
 |                              right_modifier * right_pixel + round_value) / | 
 |                             dest_scale); | 
 |  | 
 |     right_modifier += source_scale; | 
 |  | 
 |     while (right_modifier > dest_scale) { | 
 |       right_modifier -= dest_scale; | 
 |       source += source_step; | 
 |       left_pixel = source[0]; | 
 |       right_pixel = source[source_step]; | 
 |     } | 
 |  | 
 |     left_modifier = dest_scale - right_modifier; | 
 |   } | 
 | } | 
 |  | 
 | /**************************************************************************** | 
 |  * | 
 |  *  ROUTINE       : Scale2D | 
 |  * | 
 |  *  INPUTS        : const unsigned char *source    : Pointer to data to be | 
 |  *                                                   scaled. | 
 |  *                  int source_pitch               : Stride of source image. | 
 |  *                  unsigned int source_width      : Width of input image. | 
 |  *                  unsigned int source_height     : Height of input image. | 
 |  *                  unsigned char *dest            : Pointer to output data | 
 |  *                                                   array. | 
 |  *                  int dest_pitch                 : Stride of destination | 
 |  *                                                   image. | 
 |  *                  unsigned int dest_width        : Width of destination image. | 
 |  *                  unsigned int dest_height       : Height of destination | 
 |  *                                                   image. | 
 |  *                  unsigned char *temp_area       : Pointer to temp work area. | 
 |  *                  unsigned char temp_area_height : Height of temp work area. | 
 |  *                  unsigned int hscale            : Horizontal scale factor | 
 |  *                                                   numerator. | 
 |  *                  unsigned int hratio            : Horizontal scale factor | 
 |  *                                                   denominator. | 
 |  *                  unsigned int vscale            : Vertical scale factor | 
 |  *                                                   numerator. | 
 |  *                  unsigned int vratio            : Vertical scale factor | 
 |  *                                                   denominator. | 
 |  *                  unsigned int interlaced        : Interlace flag. | 
 |  * | 
 |  *  OUTPUTS       : None. | 
 |  * | 
 |  *  RETURNS       : void | 
 |  * | 
 |  *  FUNCTION      : Performs 2-tap linear interpolation in two dimensions. | 
 |  * | 
 |  *  SPECIAL NOTES : Expansion is performed one band at a time to help with | 
 |  *                  caching. | 
 |  * | 
 |  ****************************************************************************/ | 
 | static void Scale2D( | 
 |     /*const*/ | 
 |     unsigned char *source, int source_pitch, unsigned int source_width, | 
 |     unsigned int source_height, unsigned char *dest, int dest_pitch, | 
 |     unsigned int dest_width, unsigned int dest_height, unsigned char *temp_area, | 
 |     unsigned char temp_area_height, unsigned int hscale, unsigned int hratio, | 
 |     unsigned int vscale, unsigned int vratio, unsigned int interlaced) { | 
 |   unsigned int i, j, k; | 
 |   unsigned int bands; | 
 |   unsigned int dest_band_height; | 
 |   unsigned int source_band_height; | 
 |  | 
 |   typedef void (*Scale1D)(const unsigned char *source, int source_step, | 
 |                           unsigned int source_scale, unsigned int source_length, | 
 |                           unsigned char *dest, int dest_step, | 
 |                           unsigned int dest_scale, unsigned int dest_length); | 
 |  | 
 |   Scale1D Scale1Dv = scale1d_c; | 
 |   Scale1D Scale1Dh = scale1d_c; | 
 |  | 
 |   void (*horiz_line_scale)(const unsigned char *, unsigned int, unsigned char *, | 
 |                            unsigned int) = NULL; | 
 |   void (*vert_band_scale)(unsigned char *, unsigned int, unsigned char *, | 
 |                           unsigned int, unsigned int) = NULL; | 
 |  | 
 |   int ratio_scalable = 1; | 
 |   int interpolation = 0; | 
 |  | 
 |   unsigned char *source_base; | 
 |   unsigned char *line_src; | 
 |  | 
 |   source_base = (unsigned char *)source; | 
 |  | 
 |   if (source_pitch < 0) { | 
 |     int offset; | 
 |  | 
 |     offset = (source_height - 1); | 
 |     offset *= source_pitch; | 
 |  | 
 |     source_base += offset; | 
 |   } | 
 |  | 
 |   /* find out the ratio for each direction */ | 
 |   switch (hratio * 10 / hscale) { | 
 |     case 8: | 
 |       /* 4-5 Scale in Width direction */ | 
 |       horiz_line_scale = aom_horizontal_line_5_4_scale; | 
 |       break; | 
 |     case 6: | 
 |       /* 3-5 Scale in Width direction */ | 
 |       horiz_line_scale = aom_horizontal_line_5_3_scale; | 
 |       break; | 
 |     case 5: | 
 |       /* 1-2 Scale in Width direction */ | 
 |       horiz_line_scale = aom_horizontal_line_2_1_scale; | 
 |       break; | 
 |     default: | 
 |       /* The ratio is not acceptable now */ | 
 |       /* throw("The ratio is not acceptable for now!"); */ | 
 |       ratio_scalable = 0; | 
 |       break; | 
 |   } | 
 |  | 
 |   switch (vratio * 10 / vscale) { | 
 |     case 8: | 
 |       /* 4-5 Scale in vertical direction */ | 
 |       vert_band_scale = aom_vertical_band_5_4_scale; | 
 |       source_band_height = 5; | 
 |       dest_band_height = 4; | 
 |       break; | 
 |     case 6: | 
 |       /* 3-5 Scale in vertical direction */ | 
 |       vert_band_scale = aom_vertical_band_5_3_scale; | 
 |       source_band_height = 5; | 
 |       dest_band_height = 3; | 
 |       break; | 
 |     case 5: | 
 |       /* 1-2 Scale in vertical direction */ | 
 |  | 
 |       if (interlaced) { | 
 |         /* if the content is interlaced, point sampling is used */ | 
 |         vert_band_scale = aom_vertical_band_2_1_scale; | 
 |       } else { | 
 |         interpolation = 1; | 
 |         /* if the content is progressive, interplo */ | 
 |         vert_band_scale = aom_vertical_band_2_1_scale_i; | 
 |       } | 
 |  | 
 |       source_band_height = 2; | 
 |       dest_band_height = 1; | 
 |       break; | 
 |     default: | 
 |       /* The ratio is not acceptable now */ | 
 |       /* throw("The ratio is not acceptable for now!"); */ | 
 |       ratio_scalable = 0; | 
 |       break; | 
 |   } | 
 |  | 
 |   if (ratio_scalable) { | 
 |     if (source_height == dest_height) { | 
 |       /* for each band of the image */ | 
 |       for (k = 0; k < dest_height; ++k) { | 
 |         horiz_line_scale(source, source_width, dest, dest_width); | 
 |         source += source_pitch; | 
 |         dest += dest_pitch; | 
 |       } | 
 |  | 
 |       return; | 
 |     } | 
 |  | 
 |     if (interpolation) { | 
 |       if (source < source_base) source = source_base; | 
 |  | 
 |       horiz_line_scale(source, source_width, temp_area, dest_width); | 
 |     } | 
 |  | 
 |     for (k = 0; k < (dest_height + dest_band_height - 1) / dest_band_height; | 
 |          ++k) { | 
 |       /* scale one band horizontally */ | 
 |       for (i = 0; i < source_band_height; ++i) { | 
 |         /* Trap case where we could read off the base of the source buffer */ | 
 |  | 
 |         line_src = source + i * source_pitch; | 
 |  | 
 |         if (line_src < source_base) line_src = source_base; | 
 |  | 
 |         horiz_line_scale(line_src, source_width, | 
 |                          temp_area + (i + 1) * dest_pitch, dest_width); | 
 |       } | 
 |  | 
 |       /* Vertical scaling is in place */ | 
 |       vert_band_scale(temp_area + dest_pitch, dest_pitch, dest, dest_pitch, | 
 |                       dest_width); | 
 |  | 
 |       if (interpolation) | 
 |         memcpy(temp_area, temp_area + source_band_height * dest_pitch, | 
 |                dest_width); | 
 |  | 
 |       /* Next band... */ | 
 |       source += (unsigned long)source_band_height * source_pitch; | 
 |       dest += (unsigned long)dest_band_height * dest_pitch; | 
 |     } | 
 |  | 
 |     return; | 
 |   } | 
 |  | 
 |   if (hscale == 2 && hratio == 1) Scale1Dh = scale1d_2t1_ps; | 
 |  | 
 |   if (vscale == 2 && vratio == 1) { | 
 |     if (interlaced) | 
 |       Scale1Dv = scale1d_2t1_ps; | 
 |     else | 
 |       Scale1Dv = scale1d_2t1_i; | 
 |   } | 
 |  | 
 |   if (source_height == dest_height) { | 
 |     /* for each band of the image */ | 
 |     for (k = 0; k < dest_height; ++k) { | 
 |       Scale1Dh(source, 1, hscale, source_width + 1, dest, 1, hratio, | 
 |                dest_width); | 
 |       source += source_pitch; | 
 |       dest += dest_pitch; | 
 |     } | 
 |  | 
 |     return; | 
 |   } | 
 |  | 
 |   if (dest_height > source_height) { | 
 |     dest_band_height = temp_area_height - 1; | 
 |     source_band_height = dest_band_height * source_height / dest_height; | 
 |   } else { | 
 |     source_band_height = temp_area_height - 1; | 
 |     dest_band_height = source_band_height * vratio / vscale; | 
 |   } | 
 |  | 
 |   /* first row needs to be done so that we can stay one row ahead for vertical | 
 |    * zoom */ | 
 |   Scale1Dh(source, 1, hscale, source_width + 1, temp_area, 1, hratio, | 
 |            dest_width); | 
 |  | 
 |   /* for each band of the image */ | 
 |   bands = (dest_height + dest_band_height - 1) / dest_band_height; | 
 |  | 
 |   for (k = 0; k < bands; ++k) { | 
 |     /* scale one band horizontally */ | 
 |     for (i = 1; i < source_band_height + 1; ++i) { | 
 |       if (k * source_band_height + i < source_height) { | 
 |         Scale1Dh(source + i * source_pitch, 1, hscale, source_width + 1, | 
 |                  temp_area + i * dest_pitch, 1, hratio, dest_width); | 
 |       } else { /*  Duplicate the last row */ | 
 |         /* copy temp_area row 0 over from last row in the past */ | 
 |         memcpy(temp_area + i * dest_pitch, temp_area + (i - 1) * dest_pitch, | 
 |                dest_pitch); | 
 |       } | 
 |     } | 
 |  | 
 |     /* scale one band vertically */ | 
 |     for (j = 0; j < dest_width; ++j) { | 
 |       Scale1Dv(&temp_area[j], dest_pitch, vscale, source_band_height + 1, | 
 |                &dest[j], dest_pitch, vratio, dest_band_height); | 
 |     } | 
 |  | 
 |     /* copy temp_area row 0 over from last row in the past */ | 
 |     memcpy(temp_area, temp_area + source_band_height * dest_pitch, dest_pitch); | 
 |  | 
 |     /* move to the next band */ | 
 |     source += source_band_height * source_pitch; | 
 |     dest += dest_band_height * dest_pitch; | 
 |   } | 
 | } | 
 |  | 
 | /**************************************************************************** | 
 |  * | 
 |  *  ROUTINE       : aom_scale_frame | 
 |  * | 
 |  *  INPUTS        : YV12_BUFFER_CONFIG *src        : Pointer to frame to be | 
 |  *                                                   scaled. | 
 |  *                  YV12_BUFFER_CONFIG *dst        : Pointer to buffer to hold | 
 |  *                                                   scaled frame. | 
 |  *                  unsigned char *temp_area       : Pointer to temp work area. | 
 |  *                  unsigned char temp_area_height : Height of temp work area. | 
 |  *                  unsigned int hscale            : Horizontal scale factor | 
 |  *                                                   numerator. | 
 |  *                  unsigned int hratio            : Horizontal scale factor | 
 |  *                                                   denominator. | 
 |  *                  unsigned int vscale            : Vertical scale factor | 
 |  *                                                   numerator. | 
 |  *                  unsigned int vratio            : Vertical scale factor | 
 |  *                                                   denominator. | 
 |  *                  unsigned int interlaced        : Interlace flag. | 
 |  * | 
 |  *  OUTPUTS       : None. | 
 |  * | 
 |  *  RETURNS       : void | 
 |  * | 
 |  *  FUNCTION      : Performs 2-tap linear interpolation in two dimensions. | 
 |  * | 
 |  *  SPECIAL NOTES : Expansion is performed one band at a time to help with | 
 |  *                  caching. | 
 |  * | 
 |  ****************************************************************************/ | 
 | void aom_scale_frame(YV12_BUFFER_CONFIG *src, YV12_BUFFER_CONFIG *dst, | 
 |                      unsigned char *temp_area, unsigned char temp_height, | 
 |                      unsigned int hscale, unsigned int hratio, | 
 |                      unsigned int vscale, unsigned int vratio, | 
 |                      unsigned int interlaced) { | 
 |   int i; | 
 |   int dw = (hscale - 1 + src->y_width * hratio) / hscale; | 
 |   int dh = (vscale - 1 + src->y_height * vratio) / vscale; | 
 |  | 
 |   /* call our internal scaling routines!! */ | 
 |   Scale2D((unsigned char *)src->y_buffer, src->y_stride, src->y_width, | 
 |           src->y_height, (unsigned char *)dst->y_buffer, dst->y_stride, dw, dh, | 
 |           temp_area, temp_height, hscale, hratio, vscale, vratio, interlaced); | 
 |  | 
 |   if (dw < (int)dst->y_width) | 
 |     for (i = 0; i < dh; ++i) | 
 |       memset(dst->y_buffer + i * dst->y_stride + dw - 1, | 
 |              dst->y_buffer[i * dst->y_stride + dw - 2], dst->y_width - dw + 1); | 
 |  | 
 |   if (dh < (int)dst->y_height) | 
 |     for (i = dh - 1; i < (int)dst->y_height; ++i) | 
 |       memcpy(dst->y_buffer + i * dst->y_stride, | 
 |              dst->y_buffer + (dh - 2) * dst->y_stride, dst->y_width + 1); | 
 |  | 
 |   Scale2D((unsigned char *)src->u_buffer, src->uv_stride, src->uv_width, | 
 |           src->uv_height, (unsigned char *)dst->u_buffer, dst->uv_stride, | 
 |           dw / 2, dh / 2, temp_area, temp_height, hscale, hratio, vscale, | 
 |           vratio, interlaced); | 
 |  | 
 |   if (dw / 2 < (int)dst->uv_width) | 
 |     for (i = 0; i < dst->uv_height; ++i) | 
 |       memset(dst->u_buffer + i * dst->uv_stride + dw / 2 - 1, | 
 |              dst->u_buffer[i * dst->uv_stride + dw / 2 - 2], | 
 |              dst->uv_width - dw / 2 + 1); | 
 |  | 
 |   if (dh / 2 < (int)dst->uv_height) | 
 |     for (i = dh / 2 - 1; i < (int)dst->y_height / 2; ++i) | 
 |       memcpy(dst->u_buffer + i * dst->uv_stride, | 
 |              dst->u_buffer + (dh / 2 - 2) * dst->uv_stride, dst->uv_width); | 
 |  | 
 |   Scale2D((unsigned char *)src->v_buffer, src->uv_stride, src->uv_width, | 
 |           src->uv_height, (unsigned char *)dst->v_buffer, dst->uv_stride, | 
 |           dw / 2, dh / 2, temp_area, temp_height, hscale, hratio, vscale, | 
 |           vratio, interlaced); | 
 |  | 
 |   if (dw / 2 < (int)dst->uv_width) | 
 |     for (i = 0; i < dst->uv_height; ++i) | 
 |       memset(dst->v_buffer + i * dst->uv_stride + dw / 2 - 1, | 
 |              dst->v_buffer[i * dst->uv_stride + dw / 2 - 2], | 
 |              dst->uv_width - dw / 2 + 1); | 
 |  | 
 |   if (dh / 2 < (int)dst->uv_height) | 
 |     for (i = dh / 2 - 1; i < (int)dst->y_height / 2; ++i) | 
 |       memcpy(dst->v_buffer + i * dst->uv_stride, | 
 |              dst->v_buffer + (dh / 2 - 2) * dst->uv_stride, dst->uv_width); | 
 | } |