Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

242 lines (211 sloc) 7.424 kb
/*
* Intel Indeo 2 codec
* Copyright (c) 2005 Konstantin Shishkov
*
* 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
* Intel Indeo 2 decoder.
*/
#define BITSTREAM_READER_LE
#include "avcodec.h"
#include "get_bits.h"
#include "indeo2data.h"
#include "libavutil/common.h"
typedef struct Ir2Context{
AVCodecContext *avctx;
AVFrame picture;
GetBitContext gb;
int decode_delta;
} Ir2Context;
#define CODE_VLC_BITS 14
static VLC ir2_vlc;
/* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
static inline int ir2_get_code(GetBitContext *gb)
{
return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
}
static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
const uint8_t *table)
{
int i;
int j;
int out = 0;
int c;
int t;
if(width&1)
return -1;
/* first line contain absolute values, other lines contain deltas */
while (out < width){
c = ir2_get_code(&ctx->gb);
if(c >= 0x80) { /* we have a run */
c -= 0x7F;
if(out + c*2 > width)
return -1;
for (i = 0; i < c * 2; i++)
dst[out++] = 0x80;
} else { /* copy two values from table */
dst[out++] = table[c * 2];
dst[out++] = table[(c * 2) + 1];
}
}
dst += stride;
for (j = 1; j < height; j++){
out = 0;
while (out < width){
c = ir2_get_code(&ctx->gb);
if(c >= 0x80) { /* we have a skip */
c -= 0x7F;
if(out + c*2 > width)
return -1;
for (i = 0; i < c * 2; i++) {
dst[out] = dst[out - stride];
out++;
}
} else { /* add two deltas from table */
t = dst[out - stride] + (table[c * 2] - 128);
t= av_clip_uint8(t);
dst[out] = t;
out++;
t = dst[out - stride] + (table[(c * 2) + 1] - 128);
t= av_clip_uint8(t);
dst[out] = t;
out++;
}
}
dst += stride;
}
return 0;
}
static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
const uint8_t *table)
{
int j;
int out = 0;
int c;
int t;
if(width&1)
return -1;
for (j = 0; j < height; j++){
out = 0;
while (out < width){
c = ir2_get_code(&ctx->gb);
if(c >= 0x80) { /* we have a skip */
c -= 0x7F;
out += c * 2;
} else { /* add two deltas from table */
t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
t= av_clip_uint8(t);
dst[out] = t;
out++;
t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
t= av_clip_uint8(t);
dst[out] = t;
out++;
}
}
dst += stride;
}
return 0;
}
static int ir2_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
Ir2Context * const s = avctx->priv_data;
AVFrame *picture = data;
AVFrame * const p = &s->picture;
int start;
p->reference = 3;
p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
if (avctx->reget_buffer(avctx, p)) {
av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
return -1;
}
start = 48; /* hardcoded for now */
if (start >= buf_size) {
av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);
return AVERROR_INVALIDDATA;
}
s->decode_delta = buf[18];
/* decide whether frame uses deltas or not */
#ifndef BITSTREAM_READER_LE
for (i = 0; i < buf_size; i++)
buf[i] = av_reverse[buf[i]];
#endif
init_get_bits(&s->gb, buf + start, (buf_size - start) * 8);
if (s->decode_delta) { /* intraframe */
ir2_decode_plane(s, avctx->width, avctx->height,
s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
/* swapped U and V */
ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
} else { /* interframe */
ir2_decode_plane_inter(s, avctx->width, avctx->height,
s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
/* swapped U and V */
ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
}
*picture = s->picture;
*data_size = sizeof(AVPicture);
return buf_size;
}
static av_cold int ir2_decode_init(AVCodecContext *avctx){
Ir2Context * const ic = avctx->priv_data;
static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
avcodec_get_frame_defaults(&ic->picture);
ic->avctx = avctx;
avctx->pix_fmt= PIX_FMT_YUV410P;
ir2_vlc.table = vlc_tables;
ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
#ifdef BITSTREAM_READER_LE
init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
&ir2_codes[0][1], 4, 2,
&ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE);
#else
init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
&ir2_codes[0][1], 4, 2,
&ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
#endif
return 0;
}
static av_cold int ir2_decode_end(AVCodecContext *avctx){
Ir2Context * const ic = avctx->priv_data;
AVFrame *pic = &ic->picture;
if (pic->data[0])
avctx->release_buffer(avctx, pic);
return 0;
}
AVCodec ff_indeo2_decoder = {
.name = "indeo2",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_INDEO2,
.priv_data_size = sizeof(Ir2Context),
.init = ir2_decode_init,
.close = ir2_decode_end,
.decode = ir2_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
};
Jump to Line
Something went wrong with that request. Please try again.