1 /*
2 * Copyright (c) 2016, Alliance for Open Media. All rights reserved.
3 *
4 * This source code is subject to the terms of the BSD 2 Clause License and
5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
6 * was not distributed with this source code in the LICENSE file, you can
7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
8 * Media Patent License 1.0 was not distributed with this source code in the
9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
10 */
11
12 #include <stdbool.h>
13 #include "common/rawenc.h"
14
15 // Number of bytes to write per batch in write_greyscale.
16 #define BATCH_SIZE 8
17
18 // Interface to writing to either a file or MD5Context. Takes a pointer to
19 // either the file or MD5Context, the buffer, the size of each element, and
20 // number of elements to write. Note that size and nmemb (last two args) must
21 // be unsigned int, as the interface to MD5Update requires that.
22 typedef void (*WRITER)(void *, const uint8_t *, unsigned int, unsigned int);
23
write_file(void * fp,const uint8_t * buffer,unsigned int size,unsigned int nmemb)24 static void write_file(void *fp, const uint8_t *buffer, unsigned int size,
25 unsigned int nmemb) {
26 fwrite(buffer, size, nmemb, (FILE *)fp);
27 }
28
write_md5(void * md5,const uint8_t * buffer,unsigned int size,unsigned int nmemb)29 static void write_md5(void *md5, const uint8_t *buffer, unsigned int size,
30 unsigned int nmemb) {
31 MD5Update((MD5Context *)md5, buffer, size * nmemb);
32 }
33
34 // Writes out n neutral chroma samples (for greyscale).
write_greyscale(const aom_image_t * img,int n,WRITER writer_func,void * file_or_md5)35 static void write_greyscale(const aom_image_t *img, int n, WRITER writer_func,
36 void *file_or_md5) {
37 // Batch 8 writes for low bit-depth, 4 writes for high bit-depth.
38 int bytes_per_sample;
39 union {
40 uint8_t u8[BATCH_SIZE];
41 uint16_t u16[BATCH_SIZE / 2];
42 } batched;
43 if (img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) {
44 bytes_per_sample = 2;
45 for (int i = 0; i < BATCH_SIZE / 2; ++i) {
46 batched.u16[i] = 1 << (img->bit_depth - 1);
47 }
48 } else {
49 bytes_per_sample = 1;
50 for (int i = 0; i < BATCH_SIZE; ++i) {
51 batched.u8[i] = 0x80;
52 }
53 }
54 const int samples_per_batch = BATCH_SIZE / bytes_per_sample;
55 const int num_batched_writes = n / samples_per_batch;
56 for (int i = 0; i < num_batched_writes; ++i) {
57 writer_func(file_or_md5, batched.u8, sizeof(uint8_t), BATCH_SIZE);
58 }
59 const int remaining = n % samples_per_batch;
60 for (int i = 0; i < remaining; ++i) {
61 writer_func(file_or_md5, batched.u8, sizeof(uint8_t), bytes_per_sample);
62 }
63 }
64
65 // Encapsulates the logic for writing raw data to either an image file or
66 // to an MD5 context.
raw_write_image_file_or_md5(const aom_image_t * img,const int * planes,const int num_planes,void * file_or_md5,WRITER writer_func)67 static void raw_write_image_file_or_md5(const aom_image_t *img,
68 const int *planes, const int num_planes,
69 void *file_or_md5, WRITER writer_func) {
70 const bool high_bitdepth = img->fmt & AOM_IMG_FMT_HIGHBITDEPTH;
71 const int bytes_per_sample = high_bitdepth ? 2 : 1;
72 for (int i = 0; i < num_planes; ++i) {
73 const int plane = planes[i];
74 const int w = aom_img_plane_width(img, plane);
75 const int h = aom_img_plane_height(img, plane);
76 // If we're on a color plane and the output is monochrome, write a greyscale
77 // value. Since there are only YUV planes, compare against Y.
78 if (img->monochrome && plane != AOM_PLANE_Y) {
79 write_greyscale(img, w * h, writer_func, file_or_md5);
80 continue;
81 }
82 const unsigned char *buf = img->planes[plane];
83 const int stride = img->stride[plane];
84 for (int y = 0; y < h; ++y) {
85 writer_func(file_or_md5, buf, bytes_per_sample, w);
86 buf += stride;
87 }
88 }
89 }
90
raw_write_image_file(const aom_image_t * img,const int * planes,const int num_planes,FILE * file)91 void raw_write_image_file(const aom_image_t *img, const int *planes,
92 const int num_planes, FILE *file) {
93 raw_write_image_file_or_md5(img, planes, num_planes, file, write_file);
94 }
95
raw_update_image_md5(const aom_image_t * img,const int * planes,const int num_planes,MD5Context * md5)96 void raw_update_image_md5(const aom_image_t *img, const int *planes,
97 const int num_planes, MD5Context *md5) {
98 raw_write_image_file_or_md5(img, planes, num_planes, md5, write_md5);
99 }
100