2d99eed1 |
/*
* SGI image decoder
* Todd Kirby <doubleshot@pacbell.net>
*
* 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
*/
|
7ffe76e5 |
#include "libavutil/imgutils.h" |
4231bbbf |
#include "libavutil/avassert.h" |
2d99eed1 |
#include "avcodec.h"
#include "bytestream.h" |
594d4d5d |
#include "internal.h" |
2d99eed1 |
#include "sgi.h"
typedef struct SgiState {
AVFrame picture; |
8401ed65 |
AVCodecContext *avctx; |
2d99eed1 |
unsigned int width;
unsigned int height;
unsigned int depth; |
fbc03004 |
unsigned int bytes_per_channel; |
2d99eed1 |
int linesize; |
4cd0bdae |
GetByteContext g; |
2d99eed1 |
} SgiState;
/**
* Expand an RLE row into a channel. |
4cd0bdae |
* @param s the current image state |
2d99eed1 |
* @param out_buf Points to one line after the output buffer. |
ea1806ce |
* @param len length of out_buf in bytes |
2d99eed1 |
* @param pixelstride pixel stride of input buffer
* @return size of output in bytes, -1 if buffer overflows
*/ |
4cd0bdae |
static int expand_rle_row(SgiState *s, uint8_t *out_buf, |
ea1806ce |
int len, int pixelstride) |
2d99eed1 |
{
unsigned char pixel, count;
unsigned char *orig = out_buf; |
8401ed65 |
uint8_t *out_end = out_buf + len; |
2d99eed1 |
|
6fd7bf7b |
while (out_buf < out_end) { |
4cd0bdae |
if (bytestream2_get_bytes_left(&s->g) < 1)
return AVERROR_INVALIDDATA;
pixel = bytestream2_get_byteu(&s->g); |
2d99eed1 |
if (!(count = (pixel & 0x7f))) { |
6fd7bf7b |
break; |
2d99eed1 |
}
/* Check for buffer overflow. */ |
8401ed65 |
if (out_end - out_buf <= pixelstride * (count - 1)) { |
ea1806ce |
av_log(s->avctx, AV_LOG_ERROR, "Invalid pixel count.\n");
return AVERROR_INVALIDDATA;
} |
2d99eed1 |
if (pixel & 0x80) {
while (count--) { |
4cd0bdae |
*out_buf = bytestream2_get_byte(&s->g); |
2d99eed1 |
out_buf += pixelstride;
}
} else { |
4cd0bdae |
pixel = bytestream2_get_byte(&s->g); |
2d99eed1 |
while (count--) {
*out_buf = pixel;
out_buf += pixelstride;
}
}
} |
6fd7bf7b |
return (out_buf - orig) / pixelstride; |
2d99eed1 |
}
/**
* Read a run length encoded SGI image.
* @param out_buf output buffer
* @param s the current image state
* @return 0 if no error, else return error number.
*/ |
4cd0bdae |
static int read_rle_sgi(uint8_t *out_buf, SgiState *s) |
2d99eed1 |
{
uint8_t *dest_row;
unsigned int len = s->height * s->depth * 4; |
4cd0bdae |
GetByteContext g_table = s->g; |
2d99eed1 |
unsigned int y, z;
unsigned int start_offset;
/* size of RLE offset and length tables */ |
4cd0bdae |
if (len * 2 > bytestream2_get_bytes_left(&s->g)) { |
2d99eed1 |
return AVERROR_INVALIDDATA;
}
for (z = 0; z < s->depth; z++) {
dest_row = out_buf;
for (y = 0; y < s->height; y++) {
dest_row -= s->linesize; |
4cd0bdae |
start_offset = bytestream2_get_be32(&g_table);
bytestream2_seek(&s->g, start_offset, SEEK_SET); |
8401ed65 |
if (expand_rle_row(s, dest_row + z, s->width*s->depth, |
4cd0bdae |
s->depth) != s->width) { |
2d99eed1 |
return AVERROR_INVALIDDATA;
}
}
}
return 0;
}
/**
* Read an uncompressed SGI image.
* @param out_buf output buffer
* @param s the current image state
* @return 0 if read success, otherwise return -1.
*/ |
0f656935 |
static int read_uncompressed_sgi(unsigned char* out_buf, SgiState *s) |
2d99eed1 |
{
int x, y, z; |
fbc03004 |
unsigned int offset = s->height * s->width * s->bytes_per_channel; |
4cd0bdae |
GetByteContext gp[4]; |
0f656935 |
uint8_t *out_end; |
2d99eed1 |
/* Test buffer size. */ |
4cd0bdae |
if (offset * s->depth > bytestream2_get_bytes_left(&s->g))
return AVERROR_INVALIDDATA;
/* Create a reader for each plane */
for (z = 0; z < s->depth; z++) {
gp[z] = s->g;
bytestream2_skip(&gp[z], z * offset); |
2d99eed1 |
}
for (y = s->height - 1; y >= 0; y--) {
out_end = out_buf + (y * s->linesize); |
4cd0bdae |
if (s->bytes_per_channel == 1) {
for (x = s->width; x > 0; x--)
for (z = 0; z < s->depth; z++)
*out_end++ = bytestream2_get_byteu(&gp[z]);
} else {
uint16_t *out16 = (uint16_t *)out_end;
for (x = s->width; x > 0; x--)
for (z = 0; z < s->depth; z++)
*out16++ = bytestream2_get_ne16u(&gp[z]); |
2d99eed1 |
}
}
return 0;
}
static int decode_frame(AVCodecContext *avctx, |
df9b9567 |
void *data, int *got_frame, |
7a00bbad |
AVPacket *avpkt) |
2d99eed1 |
{
SgiState *s = avctx->priv_data;
AVFrame *picture = data;
AVFrame *p = &s->picture; |
fbc03004 |
unsigned int dimension, rle; |
2d99eed1 |
int ret = 0;
uint8_t *out_buf, *out_end;
|
4cd0bdae |
bytestream2_init(&s->g, avpkt->data, avpkt->size);
if (bytestream2_get_bytes_left(&s->g) < SGI_HEADER_SIZE) {
av_log(avctx, AV_LOG_ERROR, "buf_size too small (%d)\n", avpkt->size);
return AVERROR_INVALIDDATA; |
2d99eed1 |
}
/* Test for SGI magic. */ |
4cd0bdae |
if (bytestream2_get_be16(&s->g) != SGI_MAGIC) { |
2d99eed1 |
av_log(avctx, AV_LOG_ERROR, "bad magic number\n"); |
4cd0bdae |
return AVERROR_INVALIDDATA; |
2d99eed1 |
}
|
4cd0bdae |
rle = bytestream2_get_byte(&s->g);
s->bytes_per_channel = bytestream2_get_byte(&s->g);
dimension = bytestream2_get_be16(&s->g);
s->width = bytestream2_get_be16(&s->g);
s->height = bytestream2_get_be16(&s->g);
s->depth = bytestream2_get_be16(&s->g); |
2d99eed1 |
|
fbc03004 |
if (s->bytes_per_channel != 1 && (s->bytes_per_channel != 2 || rle)) { |
2d99eed1 |
av_log(avctx, AV_LOG_ERROR, "wrong channel number\n");
return -1;
}
/* Check for supported image dimensions. */
if (dimension != 2 && dimension != 3) {
av_log(avctx, AV_LOG_ERROR, "wrong dimension number\n");
return -1;
}
if (s->depth == SGI_GRAYSCALE) { |
716d413c |
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_GRAY16BE : AV_PIX_FMT_GRAY8; |
2d99eed1 |
} else if (s->depth == SGI_RGB) { |
716d413c |
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGB48BE : AV_PIX_FMT_RGB24; |
0b1f20e2 |
} else if (s->depth == SGI_RGBA) { |
ac627b3d |
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGBA64BE : AV_PIX_FMT_RGBA; |
2d99eed1 |
} else {
av_log(avctx, AV_LOG_ERROR, "wrong picture format\n");
return -1;
}
|
e16f217c |
if (av_image_check_size(s->width, s->height, 0, avctx)) |
2d99eed1 |
return -1;
avcodec_set_dimensions(avctx, s->width, s->height);
if (p->data[0])
avctx->release_buffer(avctx, p);
p->reference = 0; |
594d4d5d |
if (ff_get_buffer(avctx, p) < 0) { |
2d99eed1 |
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed.\n");
return -1;
}
|
ce5e49b0 |
p->pict_type = AV_PICTURE_TYPE_I; |
2d99eed1 |
p->key_frame = 1;
out_buf = p->data[0];
out_end = out_buf + p->linesize[0] * s->height;
s->linesize = p->linesize[0];
/* Skip header. */ |
4cd0bdae |
bytestream2_seek(&s->g, SGI_HEADER_SIZE, SEEK_SET); |
2d99eed1 |
if (rle) { |
4cd0bdae |
ret = read_rle_sgi(out_end, s); |
2d99eed1 |
} else { |
0f656935 |
ret = read_uncompressed_sgi(out_buf, s); |
2d99eed1 |
}
if (ret == 0) {
*picture = s->picture; |
df9b9567 |
*got_frame = 1; |
4cd0bdae |
return avpkt->size; |
2d99eed1 |
} else { |
4cd0bdae |
return ret; |
2d99eed1 |
}
}
|
98a6fff9 |
static av_cold int sgi_init(AVCodecContext *avctx){ |
2d99eed1 |
SgiState *s = avctx->priv_data;
|
4310ba27 |
s->avctx = avctx;
|
2d99eed1 |
avcodec_get_frame_defaults(&s->picture);
avctx->coded_frame = &s->picture;
return 0;
}
|
98a6fff9 |
static av_cold int sgi_end(AVCodecContext *avctx) |
2d99eed1 |
{
SgiState * const s = avctx->priv_data;
if (s->picture.data[0])
avctx->release_buffer(avctx, &s->picture);
return 0;
}
|
e7e2df27 |
AVCodec ff_sgi_decoder = { |
ec6402b7 |
.name = "sgi",
.type = AVMEDIA_TYPE_VIDEO, |
36ef5369 |
.id = AV_CODEC_ID_SGI, |
ec6402b7 |
.priv_data_size = sizeof(SgiState),
.init = sgi_init,
.close = sgi_end,
.decode = decode_frame, |
00c3b67b |
.long_name = NULL_IF_CONFIG_SMALL("SGI image"), |
f174fbac |
.capabilities = CODEC_CAP_DR1, |
2d99eed1 |
}; |