FFmpeg/libavfilter/framepool.c

/*
 * This file is part of FFmpeg.
 *
 * Copyright (c) 2015 Matthieu Bouron <matthieu.bouron stupeflix.com>
 *
 * 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
 */

#include "framepool.h"
#include "libavutil/avassert.h"
#include "libavutil/buffer.h"
#include "libavutil/frame.h"
#include "libavutil/imgutils.h"
#include "libavutil/mem.h"
#include "libavutil/pixfmt.h"

struct FFVideoFramePool {

    int width;
    int height;
    int format;
    int align;
    int linesize[4];
    AVBufferPool *pools[4];

};

FFVideoFramePool *ff_video_frame_pool_init(AVBufferRef* (*alloc)(int size),
                                           int width,
                                           int height,
                                           enum AVPixelFormat format,
                                           int align)
{
    int i, ret;
    FFVideoFramePool *pool;
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(format);

    if (!desc)
        return NULL;

    pool = av_mallocz(sizeof(FFVideoFramePool));
    if (!pool)
        return NULL;

    pool->width = width;
    pool->height = height;
    pool->format = format;
    pool->align = align;

    if ((ret = av_image_check_size(width, height, 0, NULL)) < 0) {
        goto fail;
    }

    if (!pool->linesize[0]) {
        for(i = 1; i <= align; i += i) {
            ret = av_image_fill_linesizes(pool->linesize, pool->format,
                                          FFALIGN(pool->width, i));
            if (ret < 0) {
                goto fail;
            }
            if (!(pool->linesize[0] & (pool->align - 1)))
                break;
        }

        for (i = 0; i < 4 && pool->linesize[i]; i++) {
            pool->linesize[i] = FFALIGN(pool->linesize[i], pool->align);
        }
    }

    for (i = 0; i < 4 && pool->linesize[i]; i++) {
        int h = FFALIGN(pool->height, 32);
        if (i == 1 || i == 2)
            h = FF_CEIL_RSHIFT(h, desc->log2_chroma_h);

        pool->pools[i] = av_buffer_pool_init(pool->linesize[i] * h + 16 + 16 - 1,
                                             alloc);
        if (!pool->pools[i])
            goto fail;
    }

    if (desc->flags & AV_PIX_FMT_FLAG_PAL ||
        desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL) {
        pool->pools[1] = av_buffer_pool_init(AVPALETTE_SIZE, alloc);
        if (!pool->pools[1])
            goto fail;
    }

    return pool;

fail:
    ff_video_frame_pool_uninit(&pool);
    return NULL;
}

int ff_video_frame_pool_get_config(FFVideoFramePool *pool,
                                   int *width,
                                   int *height,
                                   enum AVPixelFormat *format,
                                   int *align)
{
    if (!pool)
        return AVERROR(EINVAL);

    *width = pool->width;
    *height = pool->height;
    *format = pool->format;
    *align = pool->align;

    return 0;
}


AVFrame *ff_video_frame_pool_get(FFVideoFramePool *pool)
{
    int i;
    AVFrame *frame;
    const AVPixFmtDescriptor *desc;

    frame = av_frame_alloc();
    if (!frame) {
        return NULL;
    }

    desc = av_pix_fmt_desc_get(pool->format);
    if (!desc) {
        goto fail;
    }

    frame->width = pool->width;
    frame->height = pool->height;
    frame->format = pool->format;

    for (i = 0; i < 4; i++) {
        frame->linesize[i] = pool->linesize[i];
        if (!pool->pools[i])
            break;

        frame->buf[i] = av_buffer_pool_get(pool->pools[i]);
        if (!frame->buf[i]) {
            goto fail;
        }

        frame->data[i] = frame->buf[i]->data;
    }

    if (desc->flags & AV_PIX_FMT_FLAG_PAL ||
        desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL) {
        enum AVPixelFormat format =
            pool->format == AV_PIX_FMT_PAL8 ? AV_PIX_FMT_BGR8 : pool->format;

        av_assert0(frame->data[1] != NULL);
        if (avpriv_set_systematic_pal2((uint32_t *)frame->data[1], format) < 0) {
            goto fail;
        }
    }

    frame->extended_data = frame->data;

    return frame;
fail:
    av_frame_free(&frame);
    return NULL;
}

void ff_video_frame_pool_uninit(FFVideoFramePool **pool)
{
    int i;

    if (!pool || !*pool)
        return;

    for (i = 0; i < 4; i++) {
        av_buffer_pool_uninit(&(*pool)->pools[i]);
    }

    av_freep(pool);
}