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/*

 * Quicktime Planar RGB (8BPS) Video Decoder

 * Copyright (C) 2003 Roberto Togni

 *

 * This file is part of Libav.

 *

 * Libav 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.

 *

 * Libav 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 Libav; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file

 * QT 8BPS Video Decoder by Roberto Togni

 * For more information about the 8BPS format, visit:

 *   http://www.pcisys.net/~melanson/codecs/

 *

 * Supports: PAL8 (RGB 8bpp, paletted)

 *         : BGR24 (RGB 24bpp) (can also output it as RGB32)

 *         : RGB32 (RGB 32bpp, 4th plane is probably alpha and it's ignored)

 *

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "libavutil/internal.h"

#include "libavutil/intreadwrite.h"

#include "avcodec.h"

#include "internal.h"

static const enum AVPixelFormat pixfmt_rgb24[] = {

    AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE };

typedef struct EightBpsContext {

    AVCodecContext *avctx;

    unsigned char planes;

    unsigned char planemap[4];

    uint32_t pal[256];

} EightBpsContext;

static int decode_frame(AVCodecContext *avctx, void *data,

                        int *got_frame, AVPacket *avpkt)

{

    AVFrame *frame = data;

    const uint8_t *buf = avpkt->data;

    int buf_size       = avpkt->size;

    EightBpsContext * const c = avctx->priv_data;

    const unsigned char *encoded = buf;

    unsigned char *pixptr, *pixptr_end;

    unsigned int height = avctx->height; // Real image height

    unsigned int dlen, p, row;

    const unsigned char *lp, *dp, *ep;

    unsigned char count;

    unsigned int px_inc;

    unsigned int planes     = c->planes;

    unsigned char *planemap = c->planemap;

    int ret;

    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {

        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

        return ret;

    }

    ep = encoded + buf_size;

    /* Set data pointer after line lengths */

    dp = encoded + planes * (height << 1);

    /* Ignore alpha plane, don't know what to do with it */

    if (planes == 4)

        planes--;

    px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_RGB32);

    for (p = 0; p < planes; p++) {

        /* Lines length pointer for this plane */

        lp = encoded + p * (height << 1);

        /* Decode a plane */

        for (row = 0; row < height; row++) {

            pixptr = frame->data[0] + row * frame->linesize[0] + planemap[p];

            pixptr_end = pixptr + frame->linesize[0];

            if (ep - lp < row * 2 + 2)

                return AVERROR_INVALIDDATA;

            dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));

            /* Decode a row of this plane */

            while (dlen > 0) {

                if (ep - dp <= 1)

                    return AVERROR_INVALIDDATA;

                if ((count = *dp++) <= 127) {

                    count++;

                    dlen -= count + 1;

                    if (pixptr_end - pixptr < count * px_inc)

                        break;

                    if (ep - dp < count)

                        return AVERROR_INVALIDDATA;

                    while (count--) {

                        *pixptr = *dp++;

                        pixptr += px_inc;

                    }

                } else {

                    count = 257 - count;

                    if (pixptr_end - pixptr < count * px_inc)

                        break;

                    while (count--) {

                        *pixptr = *dp;

                        pixptr += px_inc;

                    }

                    dp++;

                    dlen -= 2;

                }

            }

        }

    }

    if (avctx->bits_per_coded_sample <= 8) {

        const uint8_t *pal = av_packet_get_side_data(avpkt,

                                                     AV_PKT_DATA_PALETTE,

                                                     NULL);

        if (pal) {

            frame->palette_has_changed = 1;

            memcpy(c->pal, pal, AVPALETTE_SIZE);

        }

        memcpy (frame->data[1], c->pal, AVPALETTE_SIZE);

    }

    *got_frame = 1;

    /* always report that the buffer was completely consumed */

    return buf_size;

}

static av_cold int decode_init(AVCodecContext *avctx)

{

    EightBpsContext * const c = avctx->priv_data;

    c->avctx       = avctx;

    switch (avctx->bits_per_coded_sample) {

    case 8:

        avctx->pix_fmt = AV_PIX_FMT_PAL8;

        c->planes      = 1;

        c->planemap[0] = 0; // 1st plane is palette indexes

        break;

    case 24:

        avctx->pix_fmt = ff_get_format(avctx, pixfmt_rgb24);

        c->planes      = 3;

        c->planemap[0] = 2; // 1st plane is red

        c->planemap[1] = 1; // 2nd plane is green

        c->planemap[2] = 0; // 3rd plane is blue

        break;

    case 32:

        avctx->pix_fmt = AV_PIX_FMT_RGB32;

        c->planes      = 4;

        /* handle planemap setup later for decoding rgb24 data as rbg32 */

        break;

    default:

        av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",

               avctx->bits_per_coded_sample);

        return AVERROR_INVALIDDATA;

    }

    if (avctx->pix_fmt == AV_PIX_FMT_RGB32) {

        c->planemap[0] = HAVE_BIGENDIAN ? 1 : 2; // 1st plane is red

        c->planemap[1] = HAVE_BIGENDIAN ? 2 : 1; // 2nd plane is green

        c->planemap[2] = HAVE_BIGENDIAN ? 3 : 0; // 3rd plane is blue

        c->planemap[3] = HAVE_BIGENDIAN ? 0 : 3; // 4th plane is alpha???

    }

    return 0;

}

AVCodec ff_eightbps_decoder = {

    .name           = "8bps",

    .long_name      = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),

    .type           = AVMEDIA_TYPE_VIDEO,

    .id             = AV_CODEC_ID_8BPS,

    .priv_data_size = sizeof(EightBpsContext),

    .init           = decode_init,

    .decode         = decode_frame,

    .capabilities   = CODEC_CAP_DR1,

};