1 #include <string.h>
2 #include "tiny-nv12-scale.h"
3
4 /* TODO: optimize this stuff later, or replace with something better. it's
5 * kind of garbage. although normally it shouldn't be called that often. plus
6 * it's nearest neighbor so not really a huge deal. at the very least it
7 * should be sse2 at some point. */
8
nv12_scale_init(nv12_scale_t * s,enum target_format format,int dst_cx,int dst_cy,int src_cx,int src_cy)9 void nv12_scale_init(nv12_scale_t *s, enum target_format format, int dst_cx,
10 int dst_cy, int src_cx, int src_cy)
11 {
12 s->format = format;
13
14 s->src_cx = src_cx;
15 s->src_cy = src_cy;
16
17 s->dst_cx = dst_cx;
18 s->dst_cy = dst_cy;
19 }
20
nv12_scale_nearest(nv12_scale_t * s,uint8_t * dst_start,const uint8_t * src)21 static void nv12_scale_nearest(nv12_scale_t *s, uint8_t *dst_start,
22 const uint8_t *src)
23 {
24 register uint8_t *dst = dst_start;
25 const int src_cx = s->src_cx;
26 const int src_cy = s->src_cy;
27 const int dst_cx = s->dst_cx;
28 const int dst_cy = s->dst_cy;
29
30 /* lum */
31 for (int y = 0; y < dst_cy; y++) {
32 const int src_line = y * src_cy / dst_cy * s->src_cx;
33
34 for (int x = 0; x < dst_cx; x++) {
35 const int src_x = x * src_cx / dst_cx;
36
37 *(dst++) = src[src_line + src_x];
38 }
39 }
40
41 src += src_cx * src_cy;
42
43 /* uv */
44 const int dst_cx_d2 = dst_cx / 2;
45 const int dst_cy_d2 = dst_cy / 2;
46
47 for (int y = 0; y < dst_cy_d2; y++) {
48 const int src_line = y * src_cy / dst_cy * src_cx;
49
50 for (int x = 0; x < dst_cx_d2; x++) {
51 const int src_x = x * src_cx / dst_cx * 2;
52 const int pos = src_line + src_x;
53
54 *(dst++) = src[pos];
55 *(dst++) = src[pos + 1];
56 }
57 }
58 }
59
nv12_scale_nearest_to_i420(nv12_scale_t * s,uint8_t * dst_start,const uint8_t * src)60 static void nv12_scale_nearest_to_i420(nv12_scale_t *s, uint8_t *dst_start,
61 const uint8_t *src)
62 {
63 register uint8_t *dst = dst_start;
64 const int src_cx = s->src_cx;
65 const int src_cy = s->src_cy;
66 const int dst_cx = s->dst_cx;
67 const int dst_cy = s->dst_cy;
68 const int size = src_cx * src_cy;
69
70 /* lum */
71 for (int y = 0; y < dst_cy; y++) {
72 const int src_line = y * src_cy / dst_cy * s->src_cx;
73
74 for (int x = 0; x < dst_cx; x++) {
75 const int src_x = x * src_cx / dst_cx;
76
77 *(dst++) = src[src_line + src_x];
78 }
79 }
80
81 src += size;
82
83 /* uv */
84 const int dst_cx_d2 = dst_cx / 2;
85 const int dst_cy_d2 = dst_cy / 2;
86
87 register uint8_t *dst2 = dst + dst_cx * dst_cy / 4;
88
89 for (int y = 0; y < dst_cy_d2; y++) {
90 const int src_line = y * src_cy / dst_cy * src_cx;
91
92 for (int x = 0; x < dst_cx_d2; x++) {
93 const int src_x = x * src_cx / dst_cx * 2;
94 const int pos = src_line + src_x;
95
96 *(dst++) = src[pos];
97 *(dst2++) = src[pos + 1];
98 }
99 }
100 }
101
nv12_convert_to_i420(nv12_scale_t * s,uint8_t * dst_start,const uint8_t * src_start)102 static void nv12_convert_to_i420(nv12_scale_t *s, uint8_t *dst_start,
103 const uint8_t *src_start)
104 {
105 const int size = s->src_cx * s->src_cy;
106 const int size_d4 = size / 4;
107
108 memcpy(dst_start, src_start, size);
109
110 register uint8_t *dst1 = dst_start + size;
111 register uint8_t *dst2 = dst1 + size_d4;
112 register uint8_t *dst_end = dst2 + size_d4;
113 register const uint8_t *src = src_start + size;
114
115 while (dst2 < dst_end) {
116 *(dst1++) = *(src++);
117 *(dst2++) = *(src++);
118 }
119 }
120
nv12_scale_nearest_to_yuy2(nv12_scale_t * s,uint8_t * dst_start,const uint8_t * src)121 static void nv12_scale_nearest_to_yuy2(nv12_scale_t *s, uint8_t *dst_start,
122 const uint8_t *src)
123 {
124 register uint8_t *dst = dst_start;
125 const int src_cx = s->src_cx;
126 const int src_cy = s->src_cy;
127 const int dst_cx = s->dst_cx;
128 const int dst_cy = s->dst_cy;
129 const int src_cx_d2 = src_cx / 2;
130 const int src_cy_d2 = src_cy / 2;
131 const int dst_cx_d2 = dst_cx / 2;
132 const int dst_cy_d2 = dst_cy / 2;
133 const int size = src_cx * src_cy;
134
135 const uint8_t *src_uv = src + size;
136
137 register int uv_flip = 0;
138
139 for (int y = 0; y < dst_cy; y++) {
140 const int src_line = y * src_cy / dst_cy * s->src_cx;
141 const int src_line_d2 =
142 y / 2 * src_cy_d2 / dst_cy_d2 * s->src_cx;
143
144 for (int x = 0; x < dst_cx; x++) {
145 const int src_x = x * src_cx / dst_cx;
146 const int src_x_d2 = x / 2 * src_cx_d2 / dst_cx_d2;
147 const int pos = src_line + src_x;
148 const int pos_uv = src_line_d2 + src_x_d2 * 2 + uv_flip;
149
150 *(dst++) = src[pos];
151 *(dst++) = src_uv[pos_uv];
152
153 uv_flip ^= 1;
154 }
155 }
156 }
157
nv12_convert_to_yuy2(nv12_scale_t * s,uint8_t * dst_start,const uint8_t * src_start)158 static void nv12_convert_to_yuy2(nv12_scale_t *s, uint8_t *dst_start,
159 const uint8_t *src_start)
160 {
161 const int size = s->src_cx * s->src_cy;
162 const int size_dst_line = s->src_cx * 4;
163
164 register const uint8_t *src_y = src_start;
165 register const uint8_t *src_uv = src_y + size;
166 register uint8_t *dst = dst_start;
167 register uint8_t *dst_end = dst + size * 2;
168
169 while (dst < dst_end) {
170 register uint8_t *dst_line_end = dst + size_dst_line;
171 const uint8_t *src_uv_start = src_uv;
172 while (dst < dst_line_end) {
173 *(dst++) = *(src_y++);
174 *(dst++) = *(src_uv++);
175 *(dst++) = *(src_y++);
176 *(dst++) = *(src_uv++);
177 }
178
179 dst_line_end = dst + size_dst_line;
180 src_uv = src_uv_start;
181 while (dst < dst_line_end) {
182 *(dst++) = *(src_y++);
183 *(dst++) = *(src_uv++);
184 *(dst++) = *(src_y++);
185 *(dst++) = *(src_uv++);
186 }
187 }
188 }
189
nv12_do_scale(nv12_scale_t * s,uint8_t * dst,const uint8_t * src)190 void nv12_do_scale(nv12_scale_t *s, uint8_t *dst, const uint8_t *src)
191 {
192 if (s->src_cx == s->dst_cx && s->src_cy == s->dst_cy) {
193 if (s->format == TARGET_FORMAT_I420)
194 nv12_convert_to_i420(s, dst, src);
195 else if (s->format == TARGET_FORMAT_YUY2)
196 nv12_convert_to_yuy2(s, dst, src);
197 else
198 memcpy(dst, src, s->src_cx * s->src_cy * 3 / 2);
199 } else {
200 if (s->format == TARGET_FORMAT_I420)
201 nv12_scale_nearest_to_i420(s, dst, src);
202 else if (s->format == TARGET_FORMAT_YUY2)
203 nv12_scale_nearest_to_yuy2(s, dst, src);
204 else
205 nv12_scale_nearest(s, dst, src);
206 }
207 }
208