| /* |
| * FITS image encoder |
| * Copyright (c) 2017 Paras Chadha |
| * |
| * 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 |
| * FITS image encoder |
| * |
| * Specification: https://fits.gsfc.nasa.gov/fits_standard.html Version 3.0 |
| * |
| * RGBA images are encoded as planes in RGBA order. So, NAXIS3 is 3 or 4 for them. |
| * Also CTYPE3 = 'RGB ' is added to the header to distinguish them from 3d images. |
| */ |
| |
| #include "libavutil/intreadwrite.h" |
| #include "avcodec.h" |
| #include "bytestream.h" |
| #include "internal.h" |
| |
| static int fits_encode_frame(AVCodecContext *avctx, AVPacket *pkt, |
| const AVFrame *pict, int *got_packet) |
| { |
| AVFrame * const p = (AVFrame *)pict; |
| uint8_t *bytestream, *bytestream_start, *ptr; |
| const uint16_t flip = (1 << 15); |
| uint64_t data_size = 0, padded_data_size = 0; |
| int ret, bitpix, naxis3 = 1, i, j, k, bytes_left; |
| int map[] = {2, 0, 1, 3}; // mapping from GBRA -> RGBA as RGBA is to be stored in FITS file.. |
| |
| switch (avctx->pix_fmt) { |
| case AV_PIX_FMT_GRAY8: |
| case AV_PIX_FMT_GRAY16BE: |
| map[0] = 0; // grayscale images should be directly mapped |
| if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) { |
| bitpix = 8; |
| } else { |
| bitpix = 16; |
| } |
| break; |
| case AV_PIX_FMT_GBRP: |
| case AV_PIX_FMT_GBRAP: |
| bitpix = 8; |
| if (avctx->pix_fmt == AV_PIX_FMT_GBRP) { |
| naxis3 = 3; |
| } else { |
| naxis3 = 4; |
| } |
| break; |
| case AV_PIX_FMT_GBRP16BE: |
| case AV_PIX_FMT_GBRAP16BE: |
| bitpix = 16; |
| if (avctx->pix_fmt == AV_PIX_FMT_GBRP16BE) { |
| naxis3 = 3; |
| } else { |
| naxis3 = 4; |
| } |
| break; |
| default: |
| av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n"); |
| return AVERROR(EINVAL); |
| } |
| |
| data_size = (bitpix >> 3) * avctx->height * avctx->width * naxis3; |
| padded_data_size = ((data_size + 2879) / 2880 ) * 2880; |
| |
| if ((ret = ff_alloc_packet2(avctx, pkt, padded_data_size, 0)) < 0) |
| return ret; |
| |
| bytestream_start = |
| bytestream = pkt->data; |
| |
| for (k = 0; k < naxis3; k++) { |
| for (i = 0; i < avctx->height; i++) { |
| ptr = p->data[map[k]] + (avctx->height - i - 1) * p->linesize[map[k]]; |
| if (bitpix == 16) { |
| for (j = 0; j < avctx->width; j++) { |
| // subtracting bzero is equivalent to first bit flip |
| bytestream_put_be16(&bytestream, AV_RB16(ptr) ^ flip); |
| ptr += 2; |
| } |
| } else { |
| memcpy(bytestream, ptr, avctx->width); |
| bytestream += avctx->width; |
| } |
| } |
| } |
| |
| bytes_left = padded_data_size - data_size; |
| memset(bytestream, 0, bytes_left); |
| bytestream += bytes_left; |
| |
| pkt->size = bytestream - bytestream_start; |
| pkt->flags |= AV_PKT_FLAG_KEY; |
| *got_packet = 1; |
| |
| return 0; |
| } |
| |
| AVCodec ff_fits_encoder = { |
| .name = "fits", |
| .long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"), |
| .type = AVMEDIA_TYPE_VIDEO, |
| .id = AV_CODEC_ID_FITS, |
| .encode2 = fits_encode_frame, |
| .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_GBRAP16BE, |
| AV_PIX_FMT_GBRP16BE, |
| AV_PIX_FMT_GBRP, |
| AV_PIX_FMT_GBRAP, |
| AV_PIX_FMT_GRAY16BE, |
| AV_PIX_FMT_GRAY8, |
| AV_PIX_FMT_NONE }, |
| }; |