/*
  * BMP image format encoder
  * Copyright (c) 2006, 2007 Michel Bardiaux
  *
  * 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 "avcodec.h"
 #include "bytestream.h"
 #include "bmp.h"
 

 static av_cold int bmp_encode_init(AVCodecContext *avctx){

     BMPContext *s = avctx->priv_data;
 
     avcodec_get_frame_defaults((AVFrame*)&s->picture);
     avctx->coded_frame = (AVFrame*)&s->picture;
 
     return 0;
 }
 
 static int bmp_encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
     BMPContext *s = avctx->priv_data;
     AVFrame *pict = data;
     AVFrame * const p= (AVFrame*)&s->picture;
     int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize;
     uint8_t *ptr;
     unsigned char* buf0 = buf;
     *p = *pict;
     p->pict_type= FF_I_TYPE;
     p->key_frame= 1;
     n_bytes_per_row = (avctx->width*3 + 3) & ~3;
     n_bytes_image = avctx->height*n_bytes_per_row;
 
     // STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER
     // and related pages.
 #define SIZE_BITMAPFILEHEADER 14
 #define SIZE_BITMAPINFOHEADER 40
     hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER;
     n_bytes = n_bytes_image + hsize;
     if(n_bytes>buf_size) {
         av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", n_bytes, buf_size);
         return -1;
     }
     bytestream_put_byte(&buf, 'B');                   // BITMAPFILEHEADER.bfType
     bytestream_put_byte(&buf, 'M');                   // do.
     bytestream_put_le32(&buf, n_bytes);               // BITMAPFILEHEADER.bfSize
     bytestream_put_le16(&buf, 0);                     // BITMAPFILEHEADER.bfReserved1
     bytestream_put_le16(&buf, 0);                     // BITMAPFILEHEADER.bfReserved2
     bytestream_put_le32(&buf, hsize);                 // BITMAPFILEHEADER.bfOffBits
     bytestream_put_le32(&buf, SIZE_BITMAPINFOHEADER); // BITMAPINFOHEADER.biSize
     bytestream_put_le32(&buf, avctx->width);          // BITMAPINFOHEADER.biWidth
     bytestream_put_le32(&buf, avctx->height);         // BITMAPINFOHEADER.biHeight
     bytestream_put_le16(&buf, 1);                     // BITMAPINFOHEADER.biPlanes
     bytestream_put_le16(&buf, 24);                    // BITMAPINFOHEADER.biBitCount
     bytestream_put_le32(&buf, BMP_RGB);               // BITMAPINFOHEADER.biCompression
     bytestream_put_le32(&buf, n_bytes_image);         // BITMAPINFOHEADER.biSizeImage
     bytestream_put_le32(&buf, 0);                     // BITMAPINFOHEADER.biXPelsPerMeter
     bytestream_put_le32(&buf, 0);                     // BITMAPINFOHEADER.biYPelsPerMeter
     bytestream_put_le32(&buf, 0);                     // BITMAPINFOHEADER.biClrUsed
     bytestream_put_le32(&buf, 0);                     // BITMAPINFOHEADER.biClrImportant
     // BMP files are bottom-to-top so we start from the end...
     ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
     buf = buf0 + hsize;
     for(i = 0; i < avctx->height; i++) {
         n = 3*avctx->width;
         memcpy(buf, ptr, n);
         buf += n;
         memset(buf, 0, n_bytes_per_row-n);
         buf += n_bytes_per_row-n;
         ptr -= p->linesize[0]; // ... and go back
     }
     return n_bytes;
 }
 
 AVCodec bmp_encoder = {
     "bmp",
     CODEC_TYPE_VIDEO,
     CODEC_ID_BMP,
     sizeof(BMPContext),
     bmp_encode_init,
     bmp_encode_frame,
     NULL, //encode_end,

     .pix_fmts= (enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_NONE},

     .long_name = NULL_IF_CONFIG_SMALL("BMP image"),

 };