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FFmpeg/libavcodec/wcmv.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

265 lines
7.7 KiB
C

/*
* WinCAM Motion Video decoder
*
* Copyright (c) 2018 Paul B Mahol
*
* 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include <zlib.h>
typedef struct WCMVContext {
int bpp;
z_stream zstream;
AVFrame *prev_frame;
uint8_t block_data[65536*8];
} WCMVContext;
static int decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
WCMVContext *s = avctx->priv_data;
AVFrame *frame = data;
int skip, blocks, zret, ret, intra = 0, flags = 0, bpp = s->bpp;
GetByteContext gb;
uint8_t *dst;
ret = inflateReset(&s->zstream);
if (ret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
return AVERROR_EXTERNAL;
}
bytestream2_init(&gb, avpkt->data, avpkt->size);
blocks = bytestream2_get_le16(&gb);
if (!blocks)
flags |= FF_REGET_BUFFER_FLAG_READONLY;
if ((ret = ff_reget_buffer(avctx, s->prev_frame, flags)) < 0)
return ret;
if (blocks > 5) {
GetByteContext bgb;
int x = 0, size;
if (blocks * 8 >= 0xFFFF)
size = bytestream2_get_le24(&gb);
else if (blocks * 8 >= 0xFF)
size = bytestream2_get_le16(&gb);
else
size = bytestream2_get_byte(&gb);
skip = bytestream2_tell(&gb);
if (size > avpkt->size - skip)
return AVERROR_INVALIDDATA;
s->zstream.next_in = avpkt->data + skip;
s->zstream.avail_in = size;
s->zstream.next_out = s->block_data;
s->zstream.avail_out = sizeof(s->block_data);
zret = inflate(&s->zstream, Z_FINISH);
if (zret != Z_STREAM_END) {
av_log(avctx, AV_LOG_ERROR,
"Inflate failed with return code: %d.\n", zret);
return AVERROR_INVALIDDATA;
}
ret = inflateReset(&s->zstream);
if (ret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
return AVERROR_EXTERNAL;
}
bytestream2_skip(&gb, size);
bytestream2_init(&bgb, s->block_data, blocks * 8);
for (int i = 0; i < blocks; i++) {
int w, h;
bytestream2_skip(&bgb, 4);
w = bytestream2_get_le16(&bgb);
h = bytestream2_get_le16(&bgb);
if (x + bpp * (int64_t)w * h > INT_MAX)
return AVERROR_INVALIDDATA;
x += bpp * w * h;
}
if (x >= 0xFFFF)
bytestream2_skip(&gb, 3);
else if (x >= 0xFF)
bytestream2_skip(&gb, 2);
else
bytestream2_skip(&gb, 1);
skip = bytestream2_tell(&gb);
s->zstream.next_in = avpkt->data + skip;
s->zstream.avail_in = avpkt->size - skip;
bytestream2_init(&gb, s->block_data, blocks * 8);
} else if (blocks) {
int x = 0;
bytestream2_seek(&gb, 2, SEEK_SET);
for (int i = 0; i < blocks; i++) {
int w, h;
bytestream2_skip(&gb, 4);
w = bytestream2_get_le16(&gb);
h = bytestream2_get_le16(&gb);
if (x + bpp * (int64_t)w * h > INT_MAX)
return AVERROR_INVALIDDATA;
x += bpp * w * h;
}
if (x >= 0xFFFF)
bytestream2_skip(&gb, 3);
else if (x >= 0xFF)
bytestream2_skip(&gb, 2);
else
bytestream2_skip(&gb, 1);
skip = bytestream2_tell(&gb);
s->zstream.next_in = avpkt->data + skip;
s->zstream.avail_in = avpkt->size - skip;
bytestream2_seek(&gb, 2, SEEK_SET);
}
if (bytestream2_get_bytes_left(&gb) < 8LL * blocks)
return AVERROR_INVALIDDATA;
if (!avctx->frame_number) {
ptrdiff_t linesize[4] = { s->prev_frame->linesize[0], 0, 0, 0 };
av_image_fill_black(s->prev_frame->data, linesize, avctx->pix_fmt, 0,
avctx->width, avctx->height);
}
for (int block = 0; block < blocks; block++) {
int x, y, w, h;
x = bytestream2_get_le16(&gb);
y = bytestream2_get_le16(&gb);
w = bytestream2_get_le16(&gb);
h = bytestream2_get_le16(&gb);
if (blocks == 1 && x == 0 && y == 0 && w == avctx->width && h == avctx->height)
intra = 1;
if (x + w > avctx->width || y + h > avctx->height)
return AVERROR_INVALIDDATA;
if (w > avctx->width || h > avctx->height)
return AVERROR_INVALIDDATA;
dst = s->prev_frame->data[0] + (avctx->height - y - 1) * s->prev_frame->linesize[0] + x * bpp;
for (int i = 0; i < h; i++) {
s->zstream.next_out = dst;
s->zstream.avail_out = w * bpp;
zret = inflate(&s->zstream, Z_SYNC_FLUSH);
if (zret != Z_OK && zret != Z_STREAM_END) {
av_log(avctx, AV_LOG_ERROR,
"Inflate failed with return code: %d.\n", zret);
return AVERROR_INVALIDDATA;
}
dst -= s->prev_frame->linesize[0];
}
}
s->prev_frame->key_frame = intra;
s->prev_frame->pict_type = intra ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
if ((ret = av_frame_ref(frame, s->prev_frame)) < 0)
return ret;
*got_frame = 1;
return avpkt->size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
WCMVContext *s = avctx->priv_data;
int zret;
switch (avctx->bits_per_coded_sample) {
case 16: avctx->pix_fmt = AV_PIX_FMT_RGB565LE; break;
case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
default: av_log(avctx, AV_LOG_ERROR, "Unsupported bits_per_coded_sample: %d\n",
avctx->bits_per_coded_sample);
return AVERROR_PATCHWELCOME;
}
s->bpp = avctx->bits_per_coded_sample >> 3;
s->zstream.zalloc = Z_NULL;
s->zstream.zfree = Z_NULL;
s->zstream.opaque = Z_NULL;
zret = inflateInit(&s->zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
return AVERROR_EXTERNAL;
}
s->prev_frame = av_frame_alloc();
if (!s->prev_frame)
return AVERROR(ENOMEM);
return 0;
}
static av_cold int decode_close(AVCodecContext *avctx)
{
WCMVContext *s = avctx->priv_data;
av_frame_free(&s->prev_frame);
inflateEnd(&s->zstream);
return 0;
}
const AVCodec ff_wcmv_decoder = {
.name = "wcmv",
.long_name = NULL_IF_CONFIG_SMALL("WinCAM Motion Video"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_WCMV,
.priv_data_size = sizeof(WCMVContext),
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
FF_CODEC_CAP_INIT_CLEANUP,
};