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Diffstat (limited to 'third_party/aom/common/rawenc.c')
-rw-r--r-- | third_party/aom/common/rawenc.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/third_party/aom/common/rawenc.c b/third_party/aom/common/rawenc.c new file mode 100644 index 0000000000..aa80d2cae3 --- /dev/null +++ b/third_party/aom/common/rawenc.c @@ -0,0 +1,99 @@ +/* + * 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. + */ + +#include <stdbool.h> +#include "common/rawenc.h" + +// Number of bytes to write per batch in write_greyscale. +#define BATCH_SIZE 8 + +// Interface to writing to either a file or MD5Context. Takes a pointer to +// either the file or MD5Context, the buffer, the size of each element, and +// number of elements to write. Note that size and nmemb (last two args) must +// be unsigned int, as the interface to MD5Update requires that. +typedef void (*WRITER)(void *, const uint8_t *, unsigned int, unsigned int); + +static void write_file(void *fp, const uint8_t *buffer, unsigned int size, + unsigned int nmemb) { + fwrite(buffer, size, nmemb, (FILE *)fp); +} + +static void write_md5(void *md5, const uint8_t *buffer, unsigned int size, + unsigned int nmemb) { + MD5Update((MD5Context *)md5, buffer, size * nmemb); +} + +// Writes out n neutral chroma samples (for greyscale). +static void write_greyscale(const aom_image_t *img, int n, WRITER writer_func, + void *file_or_md5) { + // Batch 8 writes for low bit-depth, 4 writes for high bit-depth. + int bytes_per_sample; + union { + uint8_t u8[BATCH_SIZE]; + uint16_t u16[BATCH_SIZE / 2]; + } batched; + if (img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) { + bytes_per_sample = 2; + for (int i = 0; i < BATCH_SIZE / 2; ++i) { + batched.u16[i] = 1 << (img->bit_depth - 1); + } + } else { + bytes_per_sample = 1; + for (int i = 0; i < BATCH_SIZE; ++i) { + batched.u8[i] = 0x80; + } + } + const int samples_per_batch = BATCH_SIZE / bytes_per_sample; + const int num_batched_writes = n / samples_per_batch; + for (int i = 0; i < num_batched_writes; ++i) { + writer_func(file_or_md5, batched.u8, sizeof(uint8_t), BATCH_SIZE); + } + const int remaining = n % samples_per_batch; + for (int i = 0; i < remaining; ++i) { + writer_func(file_or_md5, batched.u8, sizeof(uint8_t), bytes_per_sample); + } +} + +// Encapsulates the logic for writing raw data to either an image file or +// to an MD5 context. +static void 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) { + const bool high_bitdepth = img->fmt & AOM_IMG_FMT_HIGHBITDEPTH; + const int bytes_per_sample = high_bitdepth ? 2 : 1; + for (int i = 0; i < num_planes; ++i) { + const int plane = planes[i]; + const int w = aom_img_plane_width(img, plane); + const int h = aom_img_plane_height(img, plane); + // If we're on a color plane and the output is monochrome, write a greyscale + // value. Since there are only YUV planes, compare against Y. + if (img->monochrome && plane != AOM_PLANE_Y) { + write_greyscale(img, w * h, writer_func, file_or_md5); + continue; + } + const unsigned char *buf = img->planes[plane]; + const int stride = img->stride[plane]; + for (int y = 0; y < h; ++y) { + writer_func(file_or_md5, buf, bytes_per_sample, w); + buf += stride; + } + } +} + +void raw_write_image_file(const aom_image_t *img, const int *planes, + const int num_planes, FILE *file) { + raw_write_image_file_or_md5(img, planes, num_planes, file, write_file); +} + +void raw_update_image_md5(const aom_image_t *img, const int *planes, + const int num_planes, MD5Context *md5) { + raw_write_image_file_or_md5(img, planes, num_planes, md5, write_md5); +} |