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FFmpeg/libavcodec/sgidec.c

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/*
* 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
*/
#include "libavutil/imgutils.h"
#include "libavutil/avassert.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include "sgi.h"
typedef struct SgiState {
unsigned int width;
unsigned int height;
unsigned int depth;
unsigned int bytes_per_channel;
int linesize;
GetByteContext g;
} SgiState;
/**
* Expand an RLE row into a channel.
* @param s the current image state
* @param out_buf Points to one line after the output buffer.
* @param out_end end of line in output buffer
* @param pixelstride pixel stride of input buffer
* @return size of output in bytes, else return error code.
*/
static int expand_rle_row(SgiState *s, uint8_t *out_buf,
uint8_t *out_end, int pixelstride)
{
unsigned char pixel, count;
unsigned char *orig = out_buf;
while (out_buf < out_end) {
if (bytestream2_get_bytes_left(&s->g) < 1)
return AVERROR_INVALIDDATA;
pixel = bytestream2_get_byteu(&s->g);
if (!(count = (pixel & 0x7f))) {
break;
}
/* Check for buffer overflow. */
if (out_end - out_buf <= pixelstride * (count - 1))
return AVERROR_INVALIDDATA;
if (pixel & 0x80) {
while (count--) {
*out_buf = bytestream2_get_byte(&s->g);
out_buf += pixelstride;
}
} else {
pixel = bytestream2_get_byte(&s->g);
while (count--) {
*out_buf = pixel;
out_buf += pixelstride;
}
}
}
return (out_buf - orig) / pixelstride;
}
/**
* 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 code.
*/
static int read_rle_sgi(uint8_t *out_buf, SgiState *s)
{
uint8_t *dest_row;
unsigned int len = s->height * s->depth * 4;
GetByteContext g_table = s->g;
unsigned int y, z;
unsigned int start_offset;
/* size of RLE offset and length tables */
if (len * 2 > bytestream2_get_bytes_left(&s->g)) {
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;
start_offset = bytestream2_get_be32(&g_table);
bytestream2_seek(&s->g, start_offset, SEEK_SET);
if (expand_rle_row(s, dest_row + z, dest_row + s->width*s->depth,
s->depth) != s->width) {
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, else return error code.
*/
static int read_uncompressed_sgi(unsigned char* out_buf, SgiState *s)
{
int x, y, z;
unsigned int offset = s->height * s->width * s->bytes_per_channel;
GetByteContext gp[4];
uint8_t *out_end;
/* Test buffer size. */
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);
}
for (y = s->height - 1; y >= 0; y--) {
out_end = out_buf + (y * s->linesize);
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]);
}
}
return 0;
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
SgiState *s = avctx->priv_data;
AVFrame *p = data;
unsigned int dimension, rle;
int ret = 0;
uint8_t *out_buf, *out_end;
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;
}
/* Test for SGI magic. */
if (bytestream2_get_be16u(&s->g) != SGI_MAGIC) {
av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
return AVERROR_INVALIDDATA;
}
rle = bytestream2_get_byteu(&s->g);
s->bytes_per_channel = bytestream2_get_byteu(&s->g);
dimension = bytestream2_get_be16u(&s->g);
s->width = bytestream2_get_be16u(&s->g);
s->height = bytestream2_get_be16u(&s->g);
s->depth = bytestream2_get_be16u(&s->g);
if (s->bytes_per_channel != 1 && (s->bytes_per_channel != 2 || rle)) {
av_log(avctx, AV_LOG_ERROR, "wrong channel number\n");
return AVERROR_INVALIDDATA;
}
/* Check for supported image dimensions. */
if (dimension != 2 && dimension != 3) {
av_log(avctx, AV_LOG_ERROR, "wrong dimension number\n");
return AVERROR_INVALIDDATA;
}
if (s->depth == SGI_GRAYSCALE) {
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_GRAY16BE : AV_PIX_FMT_GRAY8;
} else if (s->depth == SGI_RGB) {
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGB48BE : AV_PIX_FMT_RGB24;
} else if (s->depth == SGI_RGBA) {
Merge commit '716d413c13981da15323c7a3821860536eefdbbb' * commit '716d413c13981da15323c7a3821860536eefdbbb': Replace PIX_FMT_* -> AV_PIX_FMT_*, PixelFormat -> AVPixelFormat Conflicts: doc/examples/muxing.c ffmpeg.h ffmpeg_filter.c ffmpeg_opt.c ffplay.c ffprobe.c libavcodec/8bps.c libavcodec/aasc.c libavcodec/aura.c libavcodec/avcodec.h libavcodec/avs.c libavcodec/bfi.c libavcodec/bmp.c libavcodec/bmpenc.c libavcodec/c93.c libavcodec/cscd.c libavcodec/cyuv.c libavcodec/dpx.c libavcodec/dpxenc.c libavcodec/eatgv.c libavcodec/escape124.c libavcodec/ffv1.c libavcodec/flashsv.c libavcodec/fraps.c libavcodec/h264.c libavcodec/huffyuv.c libavcodec/iff.c libavcodec/imgconvert.c libavcodec/indeo3.c libavcodec/kmvc.c libavcodec/libopenjpegdec.c libavcodec/libopenjpegenc.c libavcodec/libx264.c libavcodec/ljpegenc.c libavcodec/mjpegdec.c libavcodec/mjpegenc.c libavcodec/motionpixels.c libavcodec/mpeg12.c libavcodec/mpeg12enc.c libavcodec/mpeg4videodec.c libavcodec/mpegvideo_enc.c libavcodec/pamenc.c libavcodec/pcxenc.c libavcodec/pgssubdec.c libavcodec/pngdec.c libavcodec/pngenc.c libavcodec/pnm.c libavcodec/pnmdec.c libavcodec/pnmenc.c libavcodec/ptx.c libavcodec/qdrw.c libavcodec/qpeg.c libavcodec/qtrleenc.c libavcodec/raw.c libavcodec/rawdec.c libavcodec/rl2.c libavcodec/sgidec.c libavcodec/sgienc.c libavcodec/snowdec.c libavcodec/snowenc.c libavcodec/sunrast.c libavcodec/targa.c libavcodec/targaenc.c libavcodec/tiff.c libavcodec/tiffenc.c libavcodec/tmv.c libavcodec/truemotion2.c libavcodec/utils.c libavcodec/vb.c libavcodec/vp3.c libavcodec/wnv1.c libavcodec/xl.c libavcodec/xwddec.c libavcodec/xwdenc.c libavcodec/yop.c libavdevice/v4l2.c libavdevice/x11grab.c libavfilter/avfilter.c libavfilter/avfilter.h libavfilter/buffersrc.c libavfilter/drawutils.c libavfilter/formats.c libavfilter/src_movie.c libavfilter/vf_ass.c libavfilter/vf_drawtext.c libavfilter/vf_fade.c libavfilter/vf_format.c libavfilter/vf_hflip.c libavfilter/vf_lut.c libavfilter/vf_overlay.c libavfilter/vf_pad.c libavfilter/vf_scale.c libavfilter/vf_transpose.c libavfilter/vf_yadif.c libavfilter/video.c libavfilter/vsrc_testsrc.c libavformat/movenc.c libavformat/mxf.h libavformat/utils.c libavformat/yuv4mpeg.c libavutil/imgutils.c libavutil/pixdesc.c libswscale/input.c libswscale/output.c libswscale/swscale_internal.h libswscale/swscale_unscaled.c libswscale/utils.c libswscale/x86/swscale_template.c libswscale/x86/yuv2rgb.c libswscale/x86/yuv2rgb_template.c libswscale/yuv2rgb.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-10-08 21:54:00 +03:00
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGBA64BE : AV_PIX_FMT_RGBA;
} else {
av_log(avctx, AV_LOG_ERROR, "wrong picture format\n");
return AVERROR_INVALIDDATA;
}
ret = ff_set_dimensions(avctx, s->width, s->height);
if (ret < 0)
return ret;
if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
return ret;
p->pict_type = AV_PICTURE_TYPE_I;
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. */
bytestream2_seek(&s->g, SGI_HEADER_SIZE, SEEK_SET);
if (rle) {
ret = read_rle_sgi(out_end, s);
} else {
ret = read_uncompressed_sgi(out_buf, s);
}
if (ret)
return ret;
*got_frame = 1;
return avpkt->size;
}
AVCodec ff_sgi_decoder = {
.name = "sgi",
.long_name = NULL_IF_CONFIG_SMALL("SGI image"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_SGI,
.priv_data_size = sizeof(SgiState),
.decode = decode_frame,
.capabilities = CODEC_CAP_DR1,
};