FFmpeg/libavcodec/pnmdec.c
2012-12-04 21:45:36 +01:00

260 lines
8.1 KiB
C

/*
* PNM image format
* Copyright (c) 2002, 2003 Fabrice Bellard
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include "put_bits.h"
#include "pnm.h"
static int pnm_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
PNMContext * const s = avctx->priv_data;
AVFrame *picture = data;
AVFrame * const p = &s->picture;
int i, j, n, linesize, h, upgrade = 0;
unsigned char *ptr;
int components, sample_len;
s->bytestream_start =
s->bytestream = buf;
s->bytestream_end = buf + buf_size;
if (ff_pnm_decode_header(avctx, s) < 0)
return -1;
if (p->data[0])
avctx->release_buffer(avctx, p);
p->reference = 0;
if (ff_get_buffer(avctx, p) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return -1;
}
p->pict_type = AV_PICTURE_TYPE_I;
p->key_frame = 1;
switch (avctx->pix_fmt) {
default:
return -1;
case AV_PIX_FMT_RGB48BE:
n = avctx->width * 6;
components=3;
sample_len=16;
goto do_read;
case AV_PIX_FMT_RGB24:
n = avctx->width * 3;
components=3;
sample_len=8;
goto do_read;
case AV_PIX_FMT_GRAY8:
n = avctx->width;
components=1;
sample_len=8;
if (s->maxval < 255)
upgrade = 1;
goto do_read;
case AV_PIX_FMT_GRAY16BE:
case AV_PIX_FMT_GRAY16LE:
n = avctx->width * 2;
components=1;
sample_len=16;
if (s->maxval < 65535)
upgrade = 2;
goto do_read;
case AV_PIX_FMT_MONOWHITE:
case AV_PIX_FMT_MONOBLACK:
n = (avctx->width + 7) >> 3;
components=1;
sample_len=1;
do_read:
ptr = p->data[0];
linesize = p->linesize[0];
if (s->bytestream + n * avctx->height > s->bytestream_end)
return -1;
if(s->type < 4){
for (i=0; i<avctx->height; i++) {
PutBitContext pb;
init_put_bits(&pb, ptr, linesize);
for(j=0; j<avctx->width * components; j++){
unsigned int c=0;
int v=0;
while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
s->bytestream++;
if(s->bytestream >= s->bytestream_end)
return -1;
do{
v= 10*v + c;
c= (*s->bytestream++) - '0';
}while(c <= 9);
put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);
}
flush_put_bits(&pb);
ptr+= linesize;
}
}else{
for (i = 0; i < avctx->height; i++) {
if (!upgrade)
memcpy(ptr, s->bytestream, n);
else if (upgrade == 1) {
unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;
for (j = 0; j < n; j++)
ptr[j] = (s->bytestream[j] * f + 64) >> 7;
} else if (upgrade == 2) {
unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;
for (j = 0; j < n / 2; j++) {
v = av_be2ne16(((uint16_t *)s->bytestream)[j]);
((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;
}
}
s->bytestream += n;
ptr += linesize;
}
}
break;
case AV_PIX_FMT_YUV420P:
{
unsigned char *ptr1, *ptr2;
n = avctx->width;
ptr = p->data[0];
linesize = p->linesize[0];
if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)
return -1;
for (i = 0; i < avctx->height; i++) {
memcpy(ptr, s->bytestream, n);
s->bytestream += n;
ptr += linesize;
}
ptr1 = p->data[1];
ptr2 = p->data[2];
n >>= 1;
h = avctx->height >> 1;
for (i = 0; i < h; i++) {
memcpy(ptr1, s->bytestream, n);
s->bytestream += n;
memcpy(ptr2, s->bytestream, n);
s->bytestream += n;
ptr1 += p->linesize[1];
ptr2 += p->linesize[2];
}
}
break;
case AV_PIX_FMT_RGB32:
ptr = p->data[0];
linesize = p->linesize[0];
if (s->bytestream + avctx->width * avctx->height * 4 > s->bytestream_end)
return -1;
for (i = 0; i < avctx->height; i++) {
int j, r, g, b, a;
for (j = 0; j < avctx->width; j++) {
r = *s->bytestream++;
g = *s->bytestream++;
b = *s->bytestream++;
a = *s->bytestream++;
((uint32_t *)ptr)[j] = (a << 24) | (r << 16) | (g << 8) | b;
}
ptr += linesize;
}
break;
}
*picture = s->picture;
*got_frame = 1;
return s->bytestream - s->bytestream_start;
}
#if CONFIG_PGM_DECODER
AVCodec ff_pgm_decoder = {
.name = "pgm",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_PGM,
.priv_data_size = sizeof(PNMContext),
.init = ff_pnm_init,
.close = ff_pnm_end,
.decode = pnm_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),
};
#endif
#if CONFIG_PGMYUV_DECODER
AVCodec ff_pgmyuv_decoder = {
.name = "pgmyuv",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_PGMYUV,
.priv_data_size = sizeof(PNMContext),
.init = ff_pnm_init,
.close = ff_pnm_end,
.decode = pnm_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),
};
#endif
#if CONFIG_PPM_DECODER
AVCodec ff_ppm_decoder = {
.name = "ppm",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_PPM,
.priv_data_size = sizeof(PNMContext),
.init = ff_pnm_init,
.close = ff_pnm_end,
.decode = pnm_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),
};
#endif
#if CONFIG_PBM_DECODER
AVCodec ff_pbm_decoder = {
.name = "pbm",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_PBM,
.priv_data_size = sizeof(PNMContext),
.init = ff_pnm_init,
.close = ff_pnm_end,
.decode = pnm_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),
};
#endif
#if CONFIG_PAM_DECODER
AVCodec ff_pam_decoder = {
.name = "pam",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_PAM,
.priv_data_size = sizeof(PNMContext),
.init = ff_pnm_init,
.close = ff_pnm_end,
.decode = pnm_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
};
#endif