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FFmpeg/libavcodec/indeo2.c
Andreas Rheinhardt a247ac640d avcodec: Constify AVCodecs
Given that the AVCodec.next pointer has now been removed, most of the
AVCodecs are not modified at all any more and can therefore be made
const (as this patch does); the only exceptions are the very few codecs
for external libraries that have a init_static_data callback.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2021-04-27 10:43:15 -03:00

275 lines
8.3 KiB
C

/*
* 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.
*/
#include "libavutil/attributes.h"
#include "libavutil/thread.h"
#define BITSTREAM_READER_LE
#include "avcodec.h"
#include "get_bits.h"
#include "indeo2data.h"
#include "internal.h"
#include "mathops.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);
}
static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst,
int pitch, const uint8_t *table)
{
int i;
int j;
int out = 0;
if ((width & 1) || width * height / (2*(IR2_CODES - 0x7F)) > get_bits_left(&ctx->gb))
return AVERROR_INVALIDDATA;
/* first line contain absolute values, other lines contain deltas */
while (out < width) {
int c = ir2_get_code(&ctx->gb);
if (c >= 0x80) { /* we have a run */
c -= 0x7F;
if (out + c*2 > width)
return AVERROR_INVALIDDATA;
for (i = 0; i < c * 2; i++)
dst[out++] = 0x80;
} else { /* copy two values from table */
if (c <= 0)
return AVERROR_INVALIDDATA;
dst[out++] = table[c * 2];
dst[out++] = table[(c * 2) + 1];
}
}
dst += pitch;
for (j = 1; j < height; j++) {
out = 0;
while (out < width) {
int c;
if (get_bits_left(&ctx->gb) <= 0)
return AVERROR_INVALIDDATA;
c = ir2_get_code(&ctx->gb);
if (c >= 0x80) { /* we have a skip */
c -= 0x7F;
if (out + c*2 > width)
return AVERROR_INVALIDDATA;
for (i = 0; i < c * 2; i++) {
dst[out] = dst[out - pitch];
out++;
}
} else { /* add two deltas from table */
int t;
if (c <= 0)
return AVERROR_INVALIDDATA;
t = dst[out - pitch] + (table[c * 2] - 128);
t = av_clip_uint8(t);
dst[out] = t;
out++;
t = dst[out - pitch] + (table[(c * 2) + 1] - 128);
t = av_clip_uint8(t);
dst[out] = t;
out++;
}
}
dst += pitch;
}
return 0;
}
static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,
int pitch, const uint8_t *table)
{
int j;
int out = 0;
int c;
int t;
if (width & 1)
return AVERROR_INVALIDDATA;
for (j = 0; j < height; j++) {
out = 0;
while (out < width) {
if (get_bits_left(&ctx->gb) <= 0)
return AVERROR_INVALIDDATA;
c = ir2_get_code(&ctx->gb);
if (c >= 0x80) { /* we have a skip */
c -= 0x7F;
out += c * 2;
} else { /* add two deltas from table */
if (c <= 0)
return AVERROR_INVALIDDATA;
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 += pitch;
}
return 0;
}
static int ir2_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
Ir2Context * const s = avctx->priv_data;
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
AVFrame *picture = data;
AVFrame * const p = s->picture;
int start, ret;
int ltab, ctab;
if ((ret = ff_reget_buffer(avctx, p, 0)) < 0)
return ret;
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 */
if ((ret = init_get_bits8(&s->gb, buf + start, buf_size - start)) < 0)
return ret;
ltab = buf[0x22] & 3;
ctab = buf[0x22] >> 2;
if (ctab > 3) {
av_log(avctx, AV_LOG_ERROR, "ctab %d is invalid\n", ctab);
return AVERROR_INVALIDDATA;
}
if (s->decode_delta) { /* intraframe */
if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,
p->data[0], p->linesize[0],
ir2_delta_table[ltab])) < 0)
return ret;
/* swapped U and V */
if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
p->data[2], p->linesize[2],
ir2_delta_table[ctab])) < 0)
return ret;
if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
p->data[1], p->linesize[1],
ir2_delta_table[ctab])) < 0)
return ret;
} else { /* interframe */
if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,
p->data[0], p->linesize[0],
ir2_delta_table[ltab])) < 0)
return ret;
/* swapped U and V */
if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
p->data[2], p->linesize[2],
ir2_delta_table[ctab])) < 0)
return ret;
if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
p->data[1], p->linesize[1],
ir2_delta_table[ctab])) < 0)
return ret;
}
if ((ret = av_frame_ref(picture, p)) < 0)
return ret;
*got_frame = 1;
return buf_size;
}
static av_cold void ir2_init_static(void)
{
INIT_VLC_STATIC_FROM_LENGTHS(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
&ir2_tab[0][1], 2, &ir2_tab[0][0], 2, 1,
0, INIT_VLC_OUTPUT_LE, 1 << CODE_VLC_BITS);
}
static av_cold int ir2_decode_init(AVCodecContext *avctx)
{
static AVOnce init_static_once = AV_ONCE_INIT;
Ir2Context * const ic = avctx->priv_data;
ic->avctx = avctx;
avctx->pix_fmt= AV_PIX_FMT_YUV410P;
ic->picture = av_frame_alloc();
if (!ic->picture)
return AVERROR(ENOMEM);
ff_thread_once(&init_static_once, ir2_init_static);
return 0;
}
static av_cold int ir2_decode_end(AVCodecContext *avctx)
{
Ir2Context * const ic = avctx->priv_data;
av_frame_free(&ic->picture);
return 0;
}
const AVCodec ff_indeo2_decoder = {
.name = "indeo2",
.long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
.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 = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};