ref: ef3cb03d8b2c73fad6743315d25b03935ed544c2
dir: /vpx/src/vpx_image.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.
*/
#include <stdlib.h>
#include <string.h>
#include "vpx/vpx_image.h"
#include "vpx/vpx_integer.h"
#include "vpx_mem/vpx_mem.h"
static vpx_image_t *img_alloc_helper(vpx_image_t *img, vpx_img_fmt_t fmt,
unsigned int d_w, unsigned int d_h,
unsigned int buf_align,
unsigned int stride_align,
unsigned char *img_data) {
unsigned int h, w, s, xcs, ycs, bps;
unsigned int stride_in_bytes;
int align;
/* Treat align==0 like align==1 */
if (!buf_align) buf_align = 1;
/* Validate alignment (must be power of 2) */
if (buf_align & (buf_align - 1)) goto fail;
/* Treat align==0 like align==1 */
if (!stride_align) stride_align = 1;
/* Validate alignment (must be power of 2) */
if (stride_align & (stride_align - 1)) goto fail;
/* Get sample size for this format */
switch (fmt) {
case VPX_IMG_FMT_I420:
case VPX_IMG_FMT_YV12: bps = 12; break;
case VPX_IMG_FMT_I422:
case VPX_IMG_FMT_I440: bps = 16; break;
case VPX_IMG_FMT_I444: bps = 24; break;
case VPX_IMG_FMT_I42016: bps = 24; break;
case VPX_IMG_FMT_I42216:
case VPX_IMG_FMT_I44016: bps = 32; break;
case VPX_IMG_FMT_I44416: bps = 48; break;
default: bps = 16; break;
}
/* Get chroma shift values for this format */
switch (fmt) {
case VPX_IMG_FMT_I420:
case VPX_IMG_FMT_YV12:
case VPX_IMG_FMT_I422:
case VPX_IMG_FMT_I42016:
case VPX_IMG_FMT_I42216: xcs = 1; break;
default: xcs = 0; break;
}
switch (fmt) {
case VPX_IMG_FMT_I420:
case VPX_IMG_FMT_I440:
case VPX_IMG_FMT_YV12:
case VPX_IMG_FMT_I42016:
case VPX_IMG_FMT_I44016: ycs = 1; break;
default: ycs = 0; break;
}
/* Calculate storage sizes. If the buffer was allocated externally, the width
* and height shouldn't be adjusted. */
w = d_w;
h = d_h;
s = (fmt & VPX_IMG_FMT_PLANAR) ? w : bps * w / 8;
s = (s + stride_align - 1) & ~(stride_align - 1);
stride_in_bytes = (fmt & VPX_IMG_FMT_HIGHBITDEPTH) ? s * 2 : s;
/* Allocate the new image */
if (!img) {
img = (vpx_image_t *)calloc(1, sizeof(vpx_image_t));
if (!img) goto fail;
img->self_allocd = 1;
} else {
memset(img, 0, sizeof(vpx_image_t));
}
img->img_data = img_data;
if (!img_data) {
uint64_t alloc_size;
/* Calculate storage sizes given the chroma subsampling */
align = (1 << xcs) - 1;
w = (d_w + align) & ~align;
align = (1 << ycs) - 1;
h = (d_h + align) & ~align;
s = (fmt & VPX_IMG_FMT_PLANAR) ? w : bps * w / 8;
s = (s + stride_align - 1) & ~(stride_align - 1);
stride_in_bytes = (fmt & VPX_IMG_FMT_HIGHBITDEPTH) ? s * 2 : s;
alloc_size = (fmt & VPX_IMG_FMT_PLANAR) ? (uint64_t)h * s * bps / 8
: (uint64_t)h * s;
if (alloc_size != (size_t)alloc_size) goto fail;
img->img_data = (uint8_t *)vpx_memalign(buf_align, (size_t)alloc_size);
img->img_data_owner = 1;
}
if (!img->img_data) goto fail;
img->fmt = fmt;
img->bit_depth = (fmt & VPX_IMG_FMT_HIGHBITDEPTH) ? 16 : 8;
img->w = w;
img->h = h;
img->x_chroma_shift = xcs;
img->y_chroma_shift = ycs;
img->bps = bps;
/* Calculate strides */
img->stride[VPX_PLANE_Y] = img->stride[VPX_PLANE_ALPHA] = stride_in_bytes;
img->stride[VPX_PLANE_U] = img->stride[VPX_PLANE_V] = stride_in_bytes >> xcs;
/* Default viewport to entire image */
if (!vpx_img_set_rect(img, 0, 0, d_w, d_h)) return img;
fail:
vpx_img_free(img);
return NULL;
}
vpx_image_t *vpx_img_alloc(vpx_image_t *img, vpx_img_fmt_t fmt,
unsigned int d_w, unsigned int d_h,
unsigned int align) {
return img_alloc_helper(img, fmt, d_w, d_h, align, align, NULL);
}
vpx_image_t *vpx_img_wrap(vpx_image_t *img, vpx_img_fmt_t fmt, unsigned int d_w,
unsigned int d_h, unsigned int stride_align,
unsigned char *img_data) {
/* By setting buf_align = 1, we don't change buffer alignment in this
* function. */
return img_alloc_helper(img, fmt, d_w, d_h, 1, stride_align, img_data);
}
int vpx_img_set_rect(vpx_image_t *img, unsigned int x, unsigned int y,
unsigned int w, unsigned int h) {
unsigned char *data;
if (x + w <= img->w && y + h <= img->h) {
img->d_w = w;
img->d_h = h;
/* Calculate plane pointers */
if (!(img->fmt & VPX_IMG_FMT_PLANAR)) {
img->planes[VPX_PLANE_PACKED] =
img->img_data + x * img->bps / 8 + y * img->stride[VPX_PLANE_PACKED];
} else {
const int bytes_per_sample =
(img->fmt & VPX_IMG_FMT_HIGHBITDEPTH) ? 2 : 1;
data = img->img_data;
if (img->fmt & VPX_IMG_FMT_HAS_ALPHA) {
img->planes[VPX_PLANE_ALPHA] =
data + x * bytes_per_sample + y * img->stride[VPX_PLANE_ALPHA];
data += img->h * img->stride[VPX_PLANE_ALPHA];
}
img->planes[VPX_PLANE_Y] =
data + x * bytes_per_sample + y * img->stride[VPX_PLANE_Y];
data += img->h * img->stride[VPX_PLANE_Y];
if (!(img->fmt & VPX_IMG_FMT_UV_FLIP)) {
img->planes[VPX_PLANE_U] =
data + (x >> img->x_chroma_shift) * bytes_per_sample +
(y >> img->y_chroma_shift) * img->stride[VPX_PLANE_U];
data += (img->h >> img->y_chroma_shift) * img->stride[VPX_PLANE_U];
img->planes[VPX_PLANE_V] =
data + (x >> img->x_chroma_shift) * bytes_per_sample +
(y >> img->y_chroma_shift) * img->stride[VPX_PLANE_V];
} else {
img->planes[VPX_PLANE_V] =
data + (x >> img->x_chroma_shift) * bytes_per_sample +
(y >> img->y_chroma_shift) * img->stride[VPX_PLANE_V];
data += (img->h >> img->y_chroma_shift) * img->stride[VPX_PLANE_V];
img->planes[VPX_PLANE_U] =
data + (x >> img->x_chroma_shift) * bytes_per_sample +
(y >> img->y_chroma_shift) * img->stride[VPX_PLANE_U];
}
}
return 0;
}
return -1;
}
void vpx_img_flip(vpx_image_t *img) {
/* Note: In the calculation pointer adjustment calculation, we want the
* rhs to be promoted to a signed type. Section 6.3.1.8 of the ISO C99
* standard indicates that if the adjustment parameter is unsigned, the
* stride parameter will be promoted to unsigned, causing errors when
* the lhs is a larger type than the rhs.
*/
img->planes[VPX_PLANE_Y] += (signed)(img->d_h - 1) * img->stride[VPX_PLANE_Y];
img->stride[VPX_PLANE_Y] = -img->stride[VPX_PLANE_Y];
img->planes[VPX_PLANE_U] += (signed)((img->d_h >> img->y_chroma_shift) - 1) *
img->stride[VPX_PLANE_U];
img->stride[VPX_PLANE_U] = -img->stride[VPX_PLANE_U];
img->planes[VPX_PLANE_V] += (signed)((img->d_h >> img->y_chroma_shift) - 1) *
img->stride[VPX_PLANE_V];
img->stride[VPX_PLANE_V] = -img->stride[VPX_PLANE_V];
img->planes[VPX_PLANE_ALPHA] +=
(signed)(img->d_h - 1) * img->stride[VPX_PLANE_ALPHA];
img->stride[VPX_PLANE_ALPHA] = -img->stride[VPX_PLANE_ALPHA];
}
void vpx_img_free(vpx_image_t *img) {
if (img) {
if (img->img_data && img->img_data_owner) vpx_free(img->img_data);
if (img->self_allocd) free(img);
}
}