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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-07 11:13:41 +02:00
FFmpeg/libavcodec/fitsdec.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

334 lines
11 KiB
C

/*
* FITS image decoder
* 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 decoder
*
* Specification: https://fits.gsfc.nasa.gov/fits_standard.html Version 3.0
*
* Support all 2d images alongwith, bzero, bscale and blank keywords.
* RGBA images are supported as NAXIS3 = 3 or 4 i.e. Planes in RGBA order. Also CTYPE = 'RGB ' should be present.
* Also to interpret data, values are linearly scaled using min-max scaling but not RGB images.
*/
#include "avcodec.h"
#include "codec_internal.h"
#include "internal.h"
#include <float.h>
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
#include "libavutil/dict.h"
#include "libavutil/opt.h"
#include "fits.h"
typedef struct FITSContext {
const AVClass *class;
int blank_val;
} FITSContext;
/**
* Calculate the data_min and data_max values from the data.
* This is called if the values are not present in the header.
* @param ptr8 pointer to the data
* @param header pointer to the header
* @param end pointer to end of packet
* @return 0 if calculated successfully otherwise AVERROR_INVALIDDATA
*/
static int fill_data_min_max(const uint8_t *ptr8, FITSHeader *header, const uint8_t *end)
{
uint8_t t8;
int16_t t16;
int32_t t32;
int64_t t64;
float tflt;
double tdbl;
int i, j;
header->data_min = DBL_MAX;
header->data_max = -DBL_MAX;
switch (header->bitpix) {
#define CASE_N(a, t, rd) \
case a: \
for (i = 0; i < header->naxisn[1]; i++) { \
for (j = 0; j < header->naxisn[0]; j++) { \
t = rd; \
if (!header->blank_found || t != header->blank) { \
if (t > header->data_max) \
header->data_max = t; \
if (t < header->data_min) \
header->data_min = t; \
} \
ptr8 += abs(a) >> 3; \
} \
} \
break
CASE_N(-64, tdbl, av_int2double(AV_RB64(ptr8)));
CASE_N(-32, tflt, av_int2float(AV_RB32(ptr8)));
CASE_N(8, t8, ptr8[0]);
CASE_N(16, t16, AV_RB16(ptr8));
CASE_N(32, t32, AV_RB32(ptr8));
CASE_N(64, t64, AV_RB64(ptr8));
default:
return AVERROR_INVALIDDATA;
}
return 0;
}
/**
* Read the fits header and store the values in FITSHeader pointed by header
* @param avctx AVCodec context
* @param ptr pointer to pointer to the data
* @param header pointer to the FITSHeader
* @param end pointer to end of packet
* @param metadata pointer to pointer to AVDictionary to store metadata
* @return 0 if calculated successfully otherwise AVERROR_INVALIDDATA
*/
static int fits_read_header(AVCodecContext *avctx, const uint8_t **ptr, FITSHeader *header,
const uint8_t *end, AVDictionary **metadata)
{
const uint8_t *ptr8 = *ptr;
int lines_read, bytes_left, i, ret;
size_t size;
lines_read = 1; // to account for first header line, SIMPLE or XTENSION which is not included in packet...
avpriv_fits_header_init(header, STATE_BITPIX);
do {
if (end - ptr8 < 80)
return AVERROR_INVALIDDATA;
ret = avpriv_fits_header_parse_line(avctx, header, ptr8, &metadata);
ptr8 += 80;
lines_read++;
} while (!ret);
if (ret < 0)
return ret;
bytes_left = (((lines_read + 35) / 36) * 36 - lines_read) * 80;
if (end - ptr8 < bytes_left)
return AVERROR_INVALIDDATA;
ptr8 += bytes_left;
if (header->rgb && (header->naxis != 3 || (header->naxisn[2] != 3 && header->naxisn[2] != 4))) {
av_log(avctx, AV_LOG_ERROR, "File contains RGB image but NAXIS = %d and NAXIS3 = %d\n", header->naxis, header->naxisn[2]);
return AVERROR_INVALIDDATA;
}
if (!header->rgb && header->naxis != 2) {
av_log(avctx, AV_LOG_ERROR, "unsupported number of dimensions, NAXIS = %d\n", header->naxis);
return AVERROR_INVALIDDATA;
}
if (header->blank_found && (header->bitpix == -32 || header->bitpix == -64)) {
av_log(avctx, AV_LOG_WARNING, "BLANK keyword found but BITPIX = %d\n. Ignoring BLANK", header->bitpix);
header->blank_found = 0;
}
size = abs(header->bitpix) >> 3;
for (i = 0; i < header->naxis; i++) {
if (size == 0 || header->naxisn[i] > SIZE_MAX / size) {
av_log(avctx, AV_LOG_ERROR, "unsupported size of FITS image");
return AVERROR_INVALIDDATA;
}
size *= header->naxisn[i];
}
if (end - ptr8 < size)
return AVERROR_INVALIDDATA;
*ptr = ptr8;
if (!header->rgb && (!header->data_min_found || !header->data_max_found)) {
ret = fill_data_min_max(ptr8, header, end);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "invalid BITPIX, %d\n", header->bitpix);
return ret;
}
} else {
/*
* instead of applying bscale and bzero to every element,
* we can do inverse transformation on data_min and data_max
*/
header->data_min = (header->data_min - header->bzero) / header->bscale;
header->data_max = (header->data_max - header->bzero) / header->bscale;
}
if (!header->rgb && header->data_min >= header->data_max) {
if (header->data_min > header->data_max) {
av_log(avctx, AV_LOG_ERROR, "data min/max (%g %g) is invalid\n", header->data_min, header->data_max);
return AVERROR_INVALIDDATA;
}
av_log(avctx, AV_LOG_WARNING, "data min/max indicates a blank image\n");
header->data_max ++;
}
return 0;
}
static int fits_decode_frame(AVCodecContext *avctx, AVFrame *p,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *ptr8 = avpkt->data, *end;
uint8_t t8;
int16_t t16;
int32_t t32;
int64_t t64;
float tflt;
double tdbl;
int ret, i, j, k;
const int map[] = {2, 0, 1, 3}; // mapping from GBRA -> RGBA as RGBA is to be stored in FITS file..
uint8_t *dst8;
uint16_t *dst16;
uint64_t t;
FITSHeader header;
FITSContext * fitsctx = avctx->priv_data;
end = ptr8 + avpkt->size;
p->metadata = NULL;
ret = fits_read_header(avctx, &ptr8, &header, end, &p->metadata);
if (ret < 0)
return ret;
if (header.rgb) {
if (header.bitpix == 8) {
if (header.naxisn[2] == 3) {
avctx->pix_fmt = AV_PIX_FMT_GBRP;
} else {
avctx->pix_fmt = AV_PIX_FMT_GBRAP;
}
} else if (header.bitpix == 16) {
if (header.naxisn[2] == 3) {
avctx->pix_fmt = AV_PIX_FMT_GBRP16;
} else {
avctx->pix_fmt = AV_PIX_FMT_GBRAP16;
}
} else {
av_log(avctx, AV_LOG_ERROR, "unsupported BITPIX = %d\n", header.bitpix);
return AVERROR_INVALIDDATA;
}
} else {
if (header.bitpix == 8) {
avctx->pix_fmt = AV_PIX_FMT_GRAY8;
} else {
avctx->pix_fmt = AV_PIX_FMT_GRAY16;
}
}
if ((ret = ff_set_dimensions(avctx, header.naxisn[0], header.naxisn[1])) < 0)
return ret;
if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
return ret;
/*
* FITS stores images with bottom row first. Therefore we have
* to fill the image from bottom to top.
*/
if (header.rgb) {
switch(header.bitpix) {
#define CASE_RGB(cas, dst, type, dref) \
case cas: \
for (k = 0; k < header.naxisn[2]; k++) { \
for (i = 0; i < avctx->height; i++) { \
dst = (type *) (p->data[map[k]] + (avctx->height - i - 1) * p->linesize[map[k]]); \
for (j = 0; j < avctx->width; j++) { \
t32 = dref(ptr8); \
if (!header.blank_found || t32 != header.blank) { \
t = t32 * header.bscale + header.bzero; \
} else { \
t = fitsctx->blank_val; \
} \
*dst++ = (type) t; \
ptr8 += cas >> 3; \
} \
} \
} \
break
CASE_RGB(8, dst8, uint8_t, *);
CASE_RGB(16, dst16, uint16_t, AV_RB16);
}
} else {
double scale = header.data_max - header.data_min;
if (scale <= 0 || !isfinite(scale)) {
scale = 1;
}
scale = 1/scale;
switch (header.bitpix) {
#define CASE_GRAY(cas, dst, type, t, rd) \
case cas: \
for (i = 0; i < avctx->height; i++) { \
dst = (type *) (p->data[0] + (avctx->height-i-1)* p->linesize[0]); \
for (j = 0; j < avctx->width; j++) { \
t = rd; \
if (!header.blank_found || t != header.blank) { \
*dst++ = lrint(((t - header.data_min) * ((1 << (sizeof(type) * 8)) - 1)) * scale); \
} else { \
*dst++ = fitsctx->blank_val; \
} \
ptr8 += abs(cas) >> 3; \
} \
} \
break
CASE_GRAY(-64, dst16, uint16_t, tdbl, av_int2double(AV_RB64(ptr8)));
CASE_GRAY(-32, dst16, uint16_t, tflt, av_int2float(AV_RB32(ptr8)));
CASE_GRAY(8, dst8, uint8_t, t8, ptr8[0]);
CASE_GRAY(16, dst16, uint16_t, t16, AV_RB16(ptr8));
CASE_GRAY(32, dst16, uint16_t, t32, AV_RB32(ptr8));
CASE_GRAY(64, dst16, uint16_t, t64, AV_RB64(ptr8));
default:
av_log(avctx, AV_LOG_ERROR, "invalid BITPIX, %d\n", header.bitpix);
return AVERROR_INVALIDDATA;
}
}
p->key_frame = 1;
p->pict_type = AV_PICTURE_TYPE_I;
*got_frame = 1;
return avpkt->size;
}
static const AVOption fits_options[] = {
{ "blank_value", "value that is used to replace BLANK pixels in data array", offsetof(FITSContext, blank_val), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 65535, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM},
{ NULL },
};
static const AVClass fits_decoder_class = {
.class_name = "FITS decoder",
.item_name = av_default_item_name,
.option = fits_options,
.version = LIBAVUTIL_VERSION_INT,
};
const FFCodec ff_fits_decoder = {
.p.name = "fits",
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_FITS,
.p.capabilities = AV_CODEC_CAP_DR1,
.p.long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"),
.p.priv_class = &fits_decoder_class,
.priv_data_size = sizeof(FITSContext),
FF_CODEC_DECODE_CB(fits_decode_frame),
};