obs-studio/libobs/media-io/video-frame.c

/******************************************************************************
    Copyright (C) 2013 by Hugh Bailey <[email protected]>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 2 of the License, or
    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/

#include "video-frame.h"

#define ALIGN_SIZE(size, align) \
	size = (((size)+(align-1)) & (~(align-1)))

/* messy code alarm */
void video_frame_init(struct video_frame *frame, enum video_format format,
		uint32_t width, uint32_t height)
{
	size_t size;
	size_t offsets[MAX_AV_PLANES];
	int    alignment = base_get_alignment();

	if (!frame) return;

	memset(frame, 0, sizeof(struct video_frame));
	memset(offsets, 0, sizeof(offsets));

	switch (format) {
	case VIDEO_FORMAT_NONE:
		return;

	case VIDEO_FORMAT_I420:
		size = width * height;
		ALIGN_SIZE(size, alignment);
		offsets[0] = size;
		size += (width/2) * (height/2);
		ALIGN_SIZE(size, alignment);
		offsets[1] = size;
		size += (width/2) * (height/2);
		ALIGN_SIZE(size, alignment);
		frame->data[0] = bmalloc(size);
		frame->data[1] = (uint8_t*)frame->data[0] + offsets[0];
		frame->data[2] = (uint8_t*)frame->data[0] + offsets[1];
		frame->linesize[0] = width;
		frame->linesize[1] = width/2;
		frame->linesize[2] = width/2;
		break;

	case VIDEO_FORMAT_NV12:
		size = width * height;
		ALIGN_SIZE(size, alignment);
		offsets[0] = size;
		size += (width/2) * (height/2) * 2;
		ALIGN_SIZE(size, alignment);
		frame->data[0] = bmalloc(size);
		frame->data[1] = (uint8_t*)frame->data[0] + offsets[0];
		frame->linesize[0] = width;
		frame->linesize[1] = width;
		break;

	case VIDEO_FORMAT_YVYU:
	case VIDEO_FORMAT_YUY2:
	case VIDEO_FORMAT_UYVY:
		size = width * height * 2;
		ALIGN_SIZE(size, alignment);
		frame->data[0] = bmalloc(size);
		frame->linesize[0] = width*2;
		break;

	case VIDEO_FORMAT_RGBA:
	case VIDEO_FORMAT_BGRA:
	case VIDEO_FORMAT_BGRX:
		size = width * height * 4;
		ALIGN_SIZE(size, alignment);
		frame->data[0] = bmalloc(size);
		frame->linesize[0] = width*4;
		break;
	}
}