ref: 11694aab66da9c4a46daac0dc3678b82232a79b9
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"
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 stride_align,
unsigned char *img_data)
{
unsigned int h, w, s, xcs, ycs, bps;
int align;
/* 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_RGB32:
case VPX_IMG_FMT_RGB32_LE:
case VPX_IMG_FMT_ARGB:
case VPX_IMG_FMT_ARGB_LE:
bps = 32;
break;
case VPX_IMG_FMT_RGB24:
case VPX_IMG_FMT_BGR24:
bps = 24;
break;
case VPX_IMG_FMT_RGB565:
case VPX_IMG_FMT_RGB565_LE:
case VPX_IMG_FMT_RGB555:
case VPX_IMG_FMT_RGB555_LE:
case VPX_IMG_FMT_UYVY:
case VPX_IMG_FMT_YUY2:
case VPX_IMG_FMT_YVYU:
bps = 16;
break;
case VPX_IMG_FMT_I420:
case VPX_IMG_FMT_YV12:
case VPX_IMG_FMT_VPXI420:
case VPX_IMG_FMT_VPXYV12:
bps = 12;
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_VPXI420:
case VPX_IMG_FMT_VPXYV12:
xcs = 1;
break;
default:
xcs = 0;
break;
}
switch (fmt)
{
case VPX_IMG_FMT_I420:
case VPX_IMG_FMT_YV12:
case VPX_IMG_FMT_VPXI420:
case VPX_IMG_FMT_VPXYV12:
ycs = 1;
break;
default:
ycs = 0;
break;
}
/* 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);
/* 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)
{
img->img_data = malloc((fmt & VPX_IMG_FMT_PLANAR) ? h * w * bps / 8 : h * s);
img->img_data_owner = 1;
}
if (!img->img_data)
goto fail;
img->fmt = fmt;
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] = s;
img->stride[VPX_PLANE_U] = img->stride[VPX_PLANE_V] = s >> 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 stride_align)
{
return img_alloc_helper(img, fmt, d_w, d_h, stride_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)
{
return img_alloc_helper(img, fmt, d_w, d_h, 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
{
data = img->img_data;
if (img->fmt & VPX_IMG_FMT_HAS_ALPHA)
{
img->planes[VPX_PLANE_ALPHA] =
data + x + y * img->stride[VPX_PLANE_ALPHA];
data += img->h * img->stride[VPX_PLANE_ALPHA];
}
img->planes[VPX_PLANE_Y] = data + x + 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)
+ (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)
+ (y >> img->y_chroma_shift) * img->stride[VPX_PLANE_V];
}
else
{
img->planes[VPX_PLANE_V] = data
+ (x >> img->x_chroma_shift)
+ (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)
+ (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)
free(img->img_data);
if (img->self_allocd)
free(img);
}
}