ffmpeg/libavcore/imgutils.c

123 lines
4.0 KiB
C

/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* misc image utilities
*/
#include "imgutils.h"
#include "libavutil/pixdesc.h"
int av_get_image_linesize(enum PixelFormat pix_fmt, int width, int plane)
{
const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
int max_step [4]; /* max pixel step for each plane */
int max_step_comp[4]; /* the component for each plane which has the max pixel step */
int s;
if (desc->flags & PIX_FMT_BITSTREAM)
return (width * (desc->comp[0].step_minus1+1) + 7) >> 3;
av_fill_image_max_pixsteps(max_step, max_step_comp, desc);
s = (max_step_comp[plane] == 1 || max_step_comp[plane] == 2) ? desc->log2_chroma_w : 0;
return max_step[plane] * (((width + (1 << s) - 1)) >> s);
}
int av_fill_image_linesizes(int linesizes[4], enum PixelFormat pix_fmt, int width)
{
int i;
const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
int max_step [4]; /* max pixel step for each plane */
int max_step_comp[4]; /* the component for each plane which has the max pixel step */
memset(linesizes, 0, 4*sizeof(linesizes[0]));
if (desc->flags & PIX_FMT_HWACCEL)
return AVERROR(EINVAL);
if (desc->flags & PIX_FMT_BITSTREAM) {
linesizes[0] = (width * (desc->comp[0].step_minus1+1) + 7) >> 3;
return 0;
}
av_fill_image_max_pixsteps(max_step, max_step_comp, desc);
for (i = 0; i < 4; i++) {
int s = (max_step_comp[i] == 1 || max_step_comp[i] == 2) ? desc->log2_chroma_w : 0;
linesizes[i] = max_step[i] * (((width + (1 << s) - 1)) >> s);
}
return 0;
}
int av_fill_image_pointers(uint8_t *data[4], enum PixelFormat pix_fmt, int height,
uint8_t *ptr, const int linesizes[4])
{
int i, total_size, size[4], has_plane[4];
const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[pix_fmt];
memset(data , 0, sizeof(data[0])*4);
memset(size , 0, sizeof(size));
memset(has_plane, 0, sizeof(has_plane));
if (desc->flags & PIX_FMT_HWACCEL)
return AVERROR(EINVAL);
data[0] = ptr;
size[0] = linesizes[0] * height;
if (desc->flags & PIX_FMT_PAL) {
size[0] = (size[0] + 3) & ~3;
data[1] = ptr + size[0]; /* palette is stored here as 256 32 bits words */
return size[0] + 256 * 4;
}
for (i = 0; i < 4; i++)
has_plane[desc->comp[i].plane] = 1;
total_size = size[0];
for (i = 1; has_plane[i] && i < 4; i++) {
int h, s = (i == 1 || i == 2) ? desc->log2_chroma_h : 0;
data[i] = data[i-1] + size[i-1];
h = (height + (1 << s) - 1) >> s;
size[i] = h * linesizes[i];
total_size += size[i];
}
return total_size;
}
typedef struct ImgUtils {
const AVClass *class;
int log_offset;
void *log_ctx;
} ImgUtils;
static const AVClass imgutils_class = { "IMGUTILS", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(ImgUtils, log_offset), offsetof(ImgUtils, log_ctx) };
int av_check_image_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
{
ImgUtils imgutils = { &imgutils_class, log_offset, log_ctx };
if ((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
return 0;
av_log(&imgutils, AV_LOG_ERROR, "Picture size %ux%u is invalid\n", w, h);
return AVERROR(EINVAL);
}