/*

 * AHX to MP2 bitstream filter

 * Copyright (c) 2024 Paul B Mahol

 *

 * 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

 * AHX to MP2 bitstream filter.

 */

#include "libavutil/intreadwrite.h"

#include "bsf.h"

#include "bsf_internal.h"

static av_cold int init(AVBSFContext *ctx)

{

    ctx->par_out->codec_id = AV_CODEC_ID_MP2;

    return 0;

}

static int filter(AVBSFContext *ctx, AVPacket *pkt)

{

    int ret;

    ret = ff_bsf_get_packet_ref(ctx, pkt);

    if (ret < 0)

        return ret;

    if (pkt->size < 1044) {

        int original_size = pkt->size;

        ret = av_grow_packet(pkt, 1044-pkt->size);

        if (ret < 0) {

            av_packet_unref(pkt);

            return ret;

        }

        memset(pkt->data + original_size, 0, 1044 - original_size);

    }

    return 0;

}

const FFBitStreamFilter ff_ahx_to_mp2_bsf = {

    .p.name         = "ahx_to_mp2",

    .p.codec_ids    = (const enum AVCodecID []){ AV_CODEC_ID_AHX, AV_CODEC_ID_NONE },

    .init           = init,

    .filter         = filter,

};