FFmpeg/libavcodec/vmixdec.c
Andreas Rheinhardt 790f793844 avutil/common: Don't auto-include mem.h
There are lots of files that don't need it: The number of object
files that actually need it went down from 2011 to 884 here.

Keep it for external users in order to not cause breakages.

Also improve the other headers a bit while just at it.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-03-31 00:08:43 +01:00

319 lines
9.0 KiB
C

/*
* vMix decoder
* Copyright (c) 2023 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/intreadwrite.h"
#include "libavutil/mem.h"
#include "libavutil/mem_internal.h"
#include "avcodec.h"
#include "codec_internal.h"
#define CACHED_BITSTREAM_READER !ARCH_X86_32
#include "golomb.h"
#include "get_bits.h"
#include "idctdsp.h"
#include "thread.h"
typedef struct SliceContext {
const uint8_t *dc_ptr;
const uint8_t *ac_ptr;
unsigned dc_size;
unsigned ac_size;
} SliceContext;
typedef struct VMIXContext {
int nb_slices;
int lshift;
int16_t factors[64];
uint8_t scan[64];
SliceContext *slices;
unsigned int slices_size;
IDCTDSPContext idsp;
} VMIXContext;
static const uint8_t quality[] = {
1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1,64,63,62,61,
60,59,58,57,56,55,54,53,52,51,
50,49,48,47,46,45,44,43,42,41,
40,39,38,37,36,35,34,33,32,31,
30,29,28,27,26,25,24,23,22,21,
20,19,18,17,16,15,14,13,12,11,
10, 9, 8, 7, 6, 5, 4, 3, 2, 1,
};
static const uint8_t quant[64] = {
16, 16, 19, 22, 22, 26, 26, 27,
16, 16, 22, 22, 26, 27, 27, 29,
19, 22, 26, 26, 27, 29, 29, 35,
22, 24, 27, 27, 29, 32, 34, 38,
26, 27, 29, 29, 32, 35, 38, 46,
27, 29, 34, 34, 35, 40, 46, 56,
29, 34, 34, 37, 40, 48, 56, 69,
34, 37, 38, 40, 48, 58, 69, 83,
};
static av_cold int decode_init(AVCodecContext *avctx)
{
VMIXContext *s = avctx->priv_data;
avctx->bits_per_raw_sample = 8;
avctx->pix_fmt = AV_PIX_FMT_YUV422P;
avctx->coded_width = FFALIGN(avctx->width, 16);
avctx->coded_height = FFALIGN(avctx->height, 16);
ff_idctdsp_init(&s->idsp, avctx);
ff_permute_scantable(s->scan, ff_zigzag_direct,
s->idsp.idct_permutation);
return 0;
}
static inline int get_se_golomb_vmix(GetBitContext *gb)
{
unsigned int buf = get_ue_golomb_long(gb);
int sign = (buf & 1) - 1;
return ((buf >> 1) ^ (~sign));
}
static int decode_dcac(AVCodecContext *avctx,
GetBitContext *dc_gb, GetBitContext *ac_gb,
unsigned *dcrun, unsigned *acrun,
AVFrame *frame, int width, int by, int plane)
{
const ptrdiff_t linesize = frame->linesize[plane];
uint8_t *dst = frame->data[plane] + by * linesize;
unsigned dc_run = *dcrun, ac_run = *acrun;
LOCAL_ALIGNED_32(int16_t, block, [64]);
VMIXContext *s = avctx->priv_data;
const int16_t *factors = s->factors;
const uint8_t *scan = s->scan;
const int add = plane ? 0 : 1024;
int i, dc_v = 0, ac_v = 0, dc = 0;
const int lshift = s->lshift;
for (int y = 0; y < 2; y++) {
for (int x = 0; x < width; x += 8) {
memset(block, 0, sizeof(*block)*64);
if (dc_run > 0) {
dc_run--;
} else {
if (get_bits_left(dc_gb) < 1)
return AVERROR_INVALIDDATA;
dc_v = get_se_golomb_vmix(dc_gb);
dc += (unsigned)dc_v;
if (!dc_v)
dc_run = get_ue_golomb_long(dc_gb);
}
for (int n = 0; n < 64; n++) {
if (ac_run > 0) {
ac_run--;
continue;
}
if (get_bits_left(ac_gb) < 1)
return AVERROR_INVALIDDATA;
ac_v = get_se_golomb_vmix(ac_gb);
i = scan[n];
block[i] = ((unsigned)ac_v * factors[i]) >> 4;
if (!ac_v)
ac_run = get_ue_golomb_long(ac_gb);
}
block[0] = ((unsigned)dc << lshift) + (unsigned)add;
s->idsp.idct_put(dst + x, linesize, block);
}
dst += 8 * linesize;
}
*dcrun = dc_run;
*acrun = ac_run;
return 0;
}
static int decode_slice(AVCodecContext *avctx, AVFrame *frame,
const uint8_t *dc_src, unsigned dc_slice_size,
const uint8_t *ac_src, unsigned ac_slice_size,
int by)
{
unsigned dc_run = 0, ac_run = 0;
GetBitContext dc_gb, ac_gb;
int ret;
ret = init_get_bits8(&dc_gb, dc_src, dc_slice_size);
if (ret < 0)
return ret;
ret = init_get_bits8(&ac_gb, ac_src, ac_slice_size);
if (ret < 0)
return ret;
for (int p = 0; p < 3; p++) {
const int rshift = !!p;
ret = decode_dcac(avctx, &dc_gb, &ac_gb,
&dc_run, &ac_run, frame,
frame->width >> rshift, by, p);
if (ret < 0)
return ret;
if (get_bits_left(&dc_gb) < 0)
return AVERROR_INVALIDDATA;
if (get_bits_left(&ac_gb) < 0)
return AVERROR_INVALIDDATA;
align_get_bits(&dc_gb);
align_get_bits(&ac_gb);
}
if (get_bits_left(&dc_gb) > 0)
return AVERROR_INVALIDDATA;
if (get_bits_left(&ac_gb) > 0)
return AVERROR_INVALIDDATA;
return 0;
}
static int decode_slices(AVCodecContext *avctx, void *arg,
int n, int thread_nb)
{
VMIXContext *s = avctx->priv_data;
const uint8_t *dc_slice_ptr = s->slices[n].dc_ptr;
const uint8_t *ac_slice_ptr = s->slices[n].ac_ptr;
unsigned dc_slice_size = s->slices[n].dc_size;
unsigned ac_slice_size = s->slices[n].ac_size;
AVFrame *frame = arg;
return decode_slice(avctx, frame, dc_slice_ptr, dc_slice_size,
ac_slice_ptr, ac_slice_size, n * 16);
}
static int decode_frame(AVCodecContext *avctx,
AVFrame *frame, int *got_frame,
AVPacket *avpkt)
{
VMIXContext *s = avctx->priv_data;
unsigned offset, q;
int ret;
if (avpkt->size <= 7)
return AVERROR_INVALIDDATA;
s->lshift = 0;
offset = 2 + avpkt->data[0];
if (offset == 5)
s->lshift = avpkt->data[1];
else if (offset != 3)
return AVERROR_INVALIDDATA;
if (s->lshift > 31)
return AVERROR_INVALIDDATA;
q = quality[FFMIN(avpkt->data[offset - 2], FF_ARRAY_ELEMS(quality)-1)];
for (int n = 0; n < 64; n++)
s->factors[n] = quant[n] * q;
s->nb_slices = (avctx->height + 15) / 16;
av_fast_mallocz(&s->slices, &s->slices_size, s->nb_slices * sizeof(*s->slices));
if (!s->slices)
return AVERROR(ENOMEM);
for (int n = 0; n < s->nb_slices; n++) {
unsigned slice_size;
if (offset + 4 > avpkt->size)
return AVERROR_INVALIDDATA;
slice_size = AV_RL32(avpkt->data + offset);
if (slice_size > avpkt->size)
return AVERROR_INVALIDDATA;
if (avpkt->size - slice_size - 4LL < offset)
return AVERROR_INVALIDDATA;
s->slices[n].dc_size = slice_size;
s->slices[n].dc_ptr = avpkt->data + offset + 4;
offset += slice_size + 4;
}
for (int n = 0; n < s->nb_slices; n++) {
unsigned slice_size;
if (offset + 4 > avpkt->size)
return AVERROR_INVALIDDATA;
slice_size = AV_RL32(avpkt->data + offset);
if (slice_size > avpkt->size)
return AVERROR_INVALIDDATA;
if (avpkt->size - slice_size - 4LL < offset)
return AVERROR_INVALIDDATA;
s->slices[n].ac_size = slice_size;
s->slices[n].ac_ptr = avpkt->data + offset + 4;
offset += slice_size + 4;
}
ret = ff_thread_get_buffer(avctx, frame, 0);
if (ret < 0)
return ret;
avctx->execute2(avctx, decode_slices, frame, NULL, s->nb_slices);
frame->pict_type = AV_PICTURE_TYPE_I;
frame->flags |= AV_FRAME_FLAG_KEY;
*got_frame = 1;
return avpkt->size;
}
static av_cold int decode_end(AVCodecContext *avctx)
{
VMIXContext *s = avctx->priv_data;
av_freep(&s->slices);
return 0;
}
const FFCodec ff_vmix_decoder = {
.p.name = "vmix",
CODEC_LONG_NAME("vMix Video"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_VMIX,
.priv_data_size = sizeof(VMIXContext),
.init = decode_init,
.close = decode_end,
FF_CODEC_DECODE_CB(decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS |
AV_CODEC_CAP_SLICE_THREADS,
};