/*
  * Quicktime Planar RGB (8BPS) Video Decoder
  * Copyright (C) 2003 Roberto Togni
  *

  * 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

  * 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 alpha)

  *
  */
 
 #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 planes     = c->planes;
     unsigned char *planemap = c->planemap;

     int ret;

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

         return ret;

     ep = encoded + buf_size;
 

     /* Set data pointer after line lengths */
     dp = encoded + planes * (height << 1);
 
     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 * planes)

                         break;

                     if (ep - dp < count)

                         return AVERROR_INVALIDDATA;

                     while (count--) {
                         *pixptr = *dp++;

                         pixptr += planes;

                     }
                 } else {
                     count = 257 - count;

                     if (pixptr_end - pixptr < count * planes)

                         break;
                     while (count--) {
                         *pixptr = *dp;

                         pixptr += planes;

                     }
                     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   = AV_CODEC_CAP_DR1,

 };