xref: /aosp_15_r20/external/libvpx/vp9/encoder/vp9_frame_scale.c (revision fb1b10ab9aebc7c7068eedab379b749d7e3900be)
1 /*
2  *  Copyright (c) 2017 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "./vp9_rtcd.h"
12 #include "./vpx_config.h"
13 #include "./vpx_dsp_rtcd.h"
14 #include "./vpx_scale_rtcd.h"
15 #include "vp9/common/vp9_blockd.h"
16 #include "vp9/encoder/vp9_encoder.h"
17 #include "vpx/vpx_codec.h"
18 #include "vpx_dsp/vpx_filter.h"
19 #include "vpx_scale/yv12config.h"
20 
vp9_scale_and_extend_frame_c(const YV12_BUFFER_CONFIG * src,YV12_BUFFER_CONFIG * dst,INTERP_FILTER filter_type,int phase_scaler)21 void vp9_scale_and_extend_frame_c(const YV12_BUFFER_CONFIG *src,
22                                   YV12_BUFFER_CONFIG *dst,
23                                   INTERP_FILTER filter_type, int phase_scaler) {
24   const int src_w = src->y_crop_width;
25   const int src_h = src->y_crop_height;
26   const uint8_t *const srcs[3] = { src->y_buffer, src->u_buffer,
27                                    src->v_buffer };
28   const int src_strides[3] = { src->y_stride, src->uv_stride, src->uv_stride };
29   uint8_t *const dsts[3] = { dst->y_buffer, dst->u_buffer, dst->v_buffer };
30   const int dst_strides[3] = { dst->y_stride, dst->uv_stride, dst->uv_stride };
31   const InterpKernel *const kernel = vp9_filter_kernels[filter_type];
32   int x, y, i;
33 
34 #if HAVE_SSSE3 || HAVE_NEON
35   // TODO(linfengz): The 4:3 specialized C code is disabled by default since
36   // it's much slower than the general version which calls vpx_scaled_2d() even
37   // if vpx_scaled_2d() is not optimized. It will only be enabled as a reference
38   // for the platforms which have faster optimization.
39   if (4 * dst->y_crop_width == 3 * src_w &&
40       4 * dst->y_crop_height == 3 * src_h) {
41     // Specialize 4 to 3 scaling.
42     // Example pixel locations.
43     // (O: Original pixel. S: Scaled pixel. X: Overlapped pixel.)
44     //      phase_scaler = 0               |      phase_scaler = 8
45     //                                     |
46     //      X     O S   O   S O     X      |      O     O     O     O     O
47     //                                     |
48     //                                     |
49     //                                     |         S       S       S
50     //                                     |
51     //                                     |
52     //      O     O     O     O     O      |      O     O     O     O     O
53     //                                     |
54     //      S       S       S       S      |
55     //                                     |
56     //                                     |
57     //                                     |         S       S       S
58     //      O     O     O     O     O      |      O     O     O     O     O
59     //                                     |
60     //                                     |
61     //                                     |
62     //      S       S       S       S      |
63     //                                     |
64     //      O     O     O     O     O      |      O     O     O     O     O
65     //                                     |         S       S       S
66     //                                     |
67     //                                     |
68     //                                     |
69     //                                     |
70     //      X     O S   O   S O     X      |      O     O     O     O     O
71 
72     const int dst_ws[3] = { dst->y_crop_width, dst->uv_crop_width,
73                             dst->uv_crop_width };
74     const int dst_hs[3] = { dst->y_crop_height, dst->uv_crop_height,
75                             dst->uv_crop_height };
76     for (i = 0; i < MAX_MB_PLANE; ++i) {
77       const int dst_w = dst_ws[i];
78       const int dst_h = dst_hs[i];
79       const int src_stride = src_strides[i];
80       const int dst_stride = dst_strides[i];
81       for (y = 0; y < dst_h; y += 3) {
82         for (x = 0; x < dst_w; x += 3) {
83           const uint8_t *src_ptr = srcs[i] + 4 * y / 3 * src_stride + 4 * x / 3;
84           uint8_t *dst_ptr = dsts[i] + y * dst_stride + x;
85 
86           // Must call c function because its optimization doesn't support 3x3.
87           vpx_scaled_2d_c(src_ptr, src_stride, dst_ptr, dst_stride, kernel,
88                           phase_scaler, 64 / 3, phase_scaler, 64 / 3, 3, 3);
89         }
90       }
91     }
92   } else
93 #endif
94   {
95     const int dst_w = dst->y_crop_width;
96     const int dst_h = dst->y_crop_height;
97 
98     // The issue b/311394513 reveals a corner case bug. vpx_scaled_2d() requires
99     // both x_step_q4 and y_step_q4 are less than or equal to 64. Otherwise, it
100     // needs to call vp9_scale_and_extend_frame_nonnormative() that supports
101     // arbitrary scaling.
102     const int x_step_q4 = 16 * src_w / dst_w;
103     const int y_step_q4 = 16 * src_h / dst_h;
104     if (x_step_q4 > 64 || y_step_q4 > 64) {
105       // This function is only called while cm->bit_depth is VPX_BITS_8.
106 #if CONFIG_VP9_HIGHBITDEPTH
107       vp9_scale_and_extend_frame_nonnormative(src, dst, (int)VPX_BITS_8);
108 #else
109       vp9_scale_and_extend_frame_nonnormative(src, dst);
110 #endif  // CONFIG_VP9_HIGHBITDEPTH
111       return;
112     }
113 
114     for (i = 0; i < MAX_MB_PLANE; ++i) {
115       const int factor = (i == 0 || i == 3 ? 1 : 2);
116       const int src_stride = src_strides[i];
117       const int dst_stride = dst_strides[i];
118       for (y = 0; y < dst_h; y += 16) {
119         const int y_q4 = y * (16 / factor) * src_h / dst_h + phase_scaler;
120         for (x = 0; x < dst_w; x += 16) {
121           const int x_q4 = x * (16 / factor) * src_w / dst_w + phase_scaler;
122           const uint8_t *src_ptr = srcs[i] +
123                                    (y / factor) * src_h / dst_h * src_stride +
124                                    (x / factor) * src_w / dst_w;
125           uint8_t *dst_ptr = dsts[i] + (y / factor) * dst_stride + (x / factor);
126 
127           vpx_scaled_2d(src_ptr, src_stride, dst_ptr, dst_stride, kernel,
128                         x_q4 & 0xf, 16 * src_w / dst_w, y_q4 & 0xf,
129                         16 * src_h / dst_h, 16 / factor, 16 / factor);
130         }
131       }
132     }
133   }
134 
135   vpx_extend_frame_borders(dst);
136 }
137