ref: e259e6951d794ca6a6f2f3c9c40c5c99818613d3
dir: /vpx_scale/generic/vpx_scale.c/
/* * Copyright (c) 2010 The WebM project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ /**************************************************************************** * * Module Title : scale.c * * Description : Image scaling functions. * ***************************************************************************/ /**************************************************************************** * Header Files ****************************************************************************/ #include "./vpx_scale_rtcd.h" #include "vpx_mem/vpx_mem.h" #include "vpx_scale/vpx_scale.h" #include "vpx_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) { unsigned int i, j; unsigned int temp; int source_pitch = source_step; (void)source_length; (void)source_scale; (void)dest_scale; source_step *= 2; dest[0] = source[0]; for (i = dest_step, j = source_step; i < dest_length * dest_step; i += dest_step, j += source_step) { temp = 8; temp += 3 * source[j - source_pitch]; temp += 10 * source[j]; temp += 3 * source[j + source_pitch]; temp >>= 4; dest[i] = (char)(temp); } } /**************************************************************************** * * 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) { unsigned int i, j; (void)source_length; (void)source_scale; (void)dest_scale; source_step *= 2; j = 0; for (i = 0; i < dest_length * dest_step; i += dest_step, j += source_step) dest[i] = source[j]; } /**************************************************************************** * * 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) { unsigned int i; unsigned int round_value = dest_scale / 2; unsigned int left_modifier = dest_scale; unsigned int right_modifier = 0; unsigned char left_pixel = *source; 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 * );*/ for (i = 0; i < dest_length * dest_step; i += dest_step) { dest[i] = (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; 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; int bands; int dest_band_height; 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 = vp8_horizontal_line_5_4_scale; break; case 6: /* 3-5 Scale in Width direction */ horiz_line_scale = vp8_horizontal_line_5_3_scale; break; case 5: /* 1-2 Scale in Width direction */ horiz_line_scale = vp8_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 = vp8_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 = vp8_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 = vp8_vertical_band_2_1_scale; } else { interpolation = 1; /* if the content is progressive, interplo */ vert_band_scale = vp8_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 < (int)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 < (int)(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 = (unsigned char *)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 < (int)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 < (int)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 < (int)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 : vpx_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 vpx_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); }