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FFmpeg/libavcodec/mvcdec.c
Andreas Rheinhardt 20f9727018 avcodec/codec_internal: Add FFCodec, hide internal part of AVCodec
Up until now, codec.h contains both public and private parts
of AVCodec. This exposes the internals of AVCodec to users
and leads them into the temptation of actually using them
and forces us to forward-declare structures and types that
users can't use at all.

This commit changes this by adding a new structure FFCodec to
codec_internal.h that extends AVCodec, i.e. contains the public
AVCodec as first member; the private fields of AVCodec are moved
to this structure, leaving codec.h clean.

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-03-21 01:33:09 +01:00

285 lines
9.7 KiB
C

/*
* Silicon Graphics Motion Video Compressor 1 & 2 decoder
* Copyright (c) 2012 Peter Ross
*
* 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
* Silicon Graphics Motion Video Compressor 1 & 2 decoder
*/
#include "config_components.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "internal.h"
typedef struct MvcContext {
int vflip;
} MvcContext;
static av_cold int mvc_decode_init(AVCodecContext *avctx)
{
MvcContext *s = avctx->priv_data;
int width = avctx->width;
int height = avctx->height;
int ret;
if (avctx->codec_id == AV_CODEC_ID_MVC1) {
width += 3;
height += 3;
}
width &= ~3;
height &= ~3;
if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
return ret;
avctx->pix_fmt = (avctx->codec_id == AV_CODEC_ID_MVC1) ? AV_PIX_FMT_RGB555
: AV_PIX_FMT_RGB32;
s->vflip = avctx->extradata_size >= 9 &&
!memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9);
return 0;
}
static int decode_mvc1(AVCodecContext *avctx, GetByteContext *gb,
uint8_t *dst_start, int width, int height, int linesize)
{
uint8_t *dst;
uint16_t v[8];
int mask, x, y, i;
for (y = 0; y < height; y += 4) {
for (x = 0; x < width; x += 4) {
if (bytestream2_get_bytes_left(gb) < 6)
return 0;
mask = bytestream2_get_be16u(gb);
v[0] = bytestream2_get_be16u(gb);
v[1] = bytestream2_get_be16u(gb);
if ((v[0] & 0x8000)) {
if (bytestream2_get_bytes_left(gb) < 12) {
av_log(avctx, AV_LOG_WARNING, "buffer overflow\n");
return AVERROR_INVALIDDATA;
}
for (i = 2; i < 8; i++)
v[i] = bytestream2_get_be16u(gb);
} else {
v[2] = v[4] = v[6] = v[0];
v[3] = v[5] = v[7] = v[1];
}
#define PIX16(target, true, false) \
i = (mask & target) ? true : false; \
AV_WN16A(dst, v[i] & 0x7FFF); \
dst += 2;
#define ROW16(row, a1, a0, b1, b0) \
dst = dst_start + (y + row) * linesize + x * 2; \
PIX16(1 << (row * 4), a1, a0) \
PIX16(1 << (row * 4 + 1), a1, a0) \
PIX16(1 << (row * 4 + 2), b1, b0) \
PIX16(1 << (row * 4 + 3), b1, b0)
ROW16(0, 0, 1, 2, 3);
ROW16(1, 0, 1, 2, 3);
ROW16(2, 4, 5, 6, 7);
ROW16(3, 4, 5, 6, 7);
}
}
return 0;
}
static void set_4x4_block(uint8_t *dst, int linesize, uint32_t pixel)
{
int i, j;
for (j = 0; j < 4; j++)
for (i = 0; i < 4; i++)
AV_WN32A(dst + j * linesize + i * 4, pixel);
}
#define PIX32(target, true, false) \
AV_WN32A(dst, (mask & target) ? v[true] : v[false]); \
dst += 4;
#define ROW32(row, a1, a0, b1, b0) \
dst = dst_start + (y + row) * linesize + x * 4; \
PIX32(1 << (row * 4), a1, a0) \
PIX32(1 << (row * 4 + 1), a1, a0) \
PIX32(1 << (row * 4 + 2), b1, b0) \
PIX32(1 << (row * 4 + 3), b1, b0)
#define MVC2_BLOCK \
ROW32(0, 1, 0, 3, 2); \
ROW32(1, 1, 0, 3, 2); \
ROW32(2, 5, 4, 7, 6); \
ROW32(3, 5, 4, 7, 6);
static int decode_mvc2(AVCodecContext *avctx, GetByteContext *gb,
uint8_t *dst_start, int width, int height,
int linesize, int vflip)
{
uint8_t *dst;
uint32_t color[128], v[8];
int w, h, nb_colors, i, x, y, p0, p1, mask;
if (bytestream2_get_bytes_left(gb) < 6)
return AVERROR_INVALIDDATA;
w = bytestream2_get_be16u(gb);
h = bytestream2_get_be16u(gb);
if ((w & ~3) != width || (h & ~3) != height)
av_log(avctx, AV_LOG_WARNING, "dimension mismatch\n");
if (bytestream2_get_byteu(gb)) {
avpriv_request_sample(avctx, "bitmap feature");
return AVERROR_PATCHWELCOME;
}
nb_colors = bytestream2_get_byteu(gb);
if (bytestream2_get_bytes_left(gb) < nb_colors * 3)
return AVERROR_INVALIDDATA;
for (i = 0; i < FFMIN(nb_colors, 128); i++)
color[i] = 0xFF000000 | bytestream2_get_be24u(gb);
if (nb_colors > 128)
bytestream2_skip(gb, (nb_colors - 128) * 3);
if (vflip) {
dst_start += (height - 1) * linesize;
linesize = -linesize;
}
x = y = 0;
while (bytestream2_get_bytes_left(gb) >= 1) {
p0 = bytestream2_get_byteu(gb);
if ((p0 & 0x80)) {
if ((p0 & 0x40)) {
p0 &= 0x3F;
p0 = (p0 << 2) | (p0 >> 4);
set_4x4_block(dst_start + y * linesize + x * 4, linesize,
0xFF000000 | (p0 << 16) | (p0 << 8) | p0);
} else {
int g, r;
p0 &= 0x3F;
p0 = (p0 << 2) | (p0 >> 4);
if (bytestream2_get_bytes_left(gb) < 2)
return AVERROR_INVALIDDATA;
g = bytestream2_get_byteu(gb);
r = bytestream2_get_byteu(gb);
set_4x4_block(dst_start + y * linesize + x * 4, linesize,
0xFF000000 | (r << 16) | (g << 8) | p0);
}
} else {
if (bytestream2_get_bytes_left(gb) < 1)
return AVERROR_INVALIDDATA;
p1 = bytestream2_get_byteu(gb);
if ((p1 & 0x80)) {
if ((p0 & 0x7F) == (p1 & 0x7F)) {
set_4x4_block(dst_start + y * linesize + x * 4, linesize,
color[p0 & 0x7F]);
} else {
if (bytestream2_get_bytes_left(gb) < 2)
return AVERROR_INVALIDDATA;
v[0] = v[2] = v[4] = v[6] = color[p0 & 0x7F];
v[1] = v[3] = v[5] = v[7] = color[p1 & 0x7F];
mask = bytestream2_get_le16u(gb);
MVC2_BLOCK
}
} else {
if (bytestream2_get_bytes_left(gb) < 8)
return AVERROR_INVALIDDATA;
v[0] = color[p0 & 0x7F];
v[1] = color[p1 & 0x7F];
for (i = 2; i < 8; i++)
v[i] = color[bytestream2_get_byteu(gb) & 0x7F];
mask = bytestream2_get_le16u(gb);
MVC2_BLOCK
}
}
x += 4;
if (x >= width) {
y += 4;
if (y >= height)
break;
x = 0;
}
}
return 0;
}
static int mvc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
AVPacket *avpkt)
{
MvcContext *s = avctx->priv_data;
AVFrame *frame = data;
GetByteContext gb;
int ret;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
bytestream2_init(&gb, avpkt->data, avpkt->size);
if (avctx->codec_id == AV_CODEC_ID_MVC1)
ret = decode_mvc1(avctx, &gb, frame->data[0],
avctx->width, avctx->height, frame->linesize[0]);
else
ret = decode_mvc2(avctx, &gb, frame->data[0],
avctx->width, avctx->height, frame->linesize[0],
s->vflip);
if (ret < 0)
return ret;
frame->pict_type = AV_PICTURE_TYPE_I;
frame->key_frame = 1;
*got_frame = 1;
return avpkt->size;
}
#if CONFIG_MVC1_DECODER
const FFCodec ff_mvc1_decoder = {
.p.name = "mvc1",
.p.long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video Compressor 1"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_MVC1,
.priv_data_size = sizeof(MvcContext),
.init = mvc_decode_init,
.decode = mvc_decode_frame,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
#endif
#if CONFIG_MVC2_DECODER
const FFCodec ff_mvc2_decoder = {
.p.name = "mvc2",
.p.long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video Compressor 2"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_MVC2,
.priv_data_size = sizeof(MvcContext),
.init = mvc_decode_init,
.decode = mvc_decode_frame,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
#endif