ffmpeg/libavcodec/fitsenc.c
Andreas Rheinhardt 4243da4ff4 avcodec/codec_internal: Use union for FFCodec decode/encode callbacks
This is possible, because every given FFCodec has to implement
exactly one of these. Doing so decreases sizeof(FFCodec) and
therefore decreases the size of the binary.
Notice that in case of position-independent code the decrease
is in .data.rel.ro, so that this translates to decreased
memory consumption.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-04-05 20:02:37 +02:00

128 lines
4.2 KiB
C

/*
* 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 "codec_internal.h"
#include "encode.h"
static int fits_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *pict, int *got_packet)
{
AVFrame * const p = (AVFrame *)pict;
uint8_t *bytestream, *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_get_encode_buffer(avctx, pkt, padded_data_size, 0)) < 0)
return ret;
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);
*got_packet = 1;
return 0;
}
const FFCodec ff_fits_encoder = {
.p.name = "fits",
.p.long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_FITS,
.p.capabilities = AV_CODEC_CAP_DR1,
FF_CODEC_ENCODE_CB(fits_encode_frame),
.p.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 },
};