/*

 * FLV decoding.

 *

 * 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

 */

#include "libavutil/imgutils.h"

#include "codec_internal.h"

#include "flvdec.h"

#include "h263dec.h"

#include "mpegvideo.h"

#include "mpegvideodec.h"

int ff_flv_decode_picture_header(H263DecContext *const h)

{

    int format, width, height;

    /* picture header */

    if (get_bits(&h->gb, 17) != 1) {

        av_log(h->c.avctx, AV_LOG_ERROR, "Bad picture start code\n");

        return AVERROR_INVALIDDATA;

    }

    format = get_bits(&h->gb, 5);

    if (format != 0 && format != 1) {

        av_log(h->c.avctx, AV_LOG_ERROR, "Bad picture format\n");

        return AVERROR_INVALIDDATA;

    }

    h->flv            = format;

    h->picture_number = get_bits(&h->gb, 8); /* picture timestamp */

    format            = get_bits(&h->gb, 3);

    switch (format) {

    case 0:

        width  = get_bits(&h->gb, 8);

        height = get_bits(&h->gb, 8);

        break;

    case 1:

        width  = get_bits(&h->gb, 16);

        height = get_bits(&h->gb, 16);

        break;

    case 2:

        width  = 352;

        height = 288;

        break;

    case 3:

        width  = 176;

        height = 144;

        break;

    case 4:

        width  = 128;

        height = 96;

        break;

    case 5:

        width  = 320;

        height = 240;

        break;

    case 6:

        width  = 160;

        height = 120;

        break;

    default:

        width = height = 0;

        break;

    }

    if (av_image_check_size(width, height, 0, h->c.avctx))

        return AVERROR(EINVAL);

    h->c.width  = width;

    h->c.height = height;

    h->c.pict_type = AV_PICTURE_TYPE_I + get_bits(&h->gb, 2);

    h->c.droppable = h->c.pict_type > AV_PICTURE_TYPE_P;

    if (h->c.droppable)

        h->c.pict_type = AV_PICTURE_TYPE_P;

    skip_bits1(&h->gb); /* deblocking flag */

    h->c.chroma_qscale = h->c.qscale = get_bits(&h->gb, 5);

    h->h263_long_vectors = 0;

    /* PEI */

    if (skip_1stop_8data_bits(&h->gb) < 0)

        return AVERROR_INVALIDDATA;

    if (h->ehc_mode)

        h->c.avctx->sample_aspect_ratio= (AVRational){1,2};

    if (h->c.avctx->debug & FF_DEBUG_PICT_INFO) {

        av_log(h->c.avctx, AV_LOG_DEBUG, "%c esc_type:%d, qp:%d num:%d\n",

               h->c.droppable ? 'D' : av_get_picture_type_char(h->c.pict_type),

               h->flv, h->c.qscale, h->picture_number);

    }

    return 0;

}

const FFCodec ff_flv_decoder = {

    .p.name         = "flv",

    CODEC_LONG_NAME("FLV / Sorenson Spark / Sorenson H.263 (Flash Video)"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_FLV1,

    .priv_data_size = sizeof(H263DecContext),

    .init           = ff_h263_decode_init,

    FF_CODEC_DECODE_CB(ff_h263_decode_frame),

    .close          = ff_mpv_decode_close,

    .p.capabilities = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,

    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP |

                      FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,

    .p.max_lowres   = 3,

};