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ffmpeg/libavcodec/magicyuv.c
Andreas Rheinhardt df3cdf4c75 avcodec: Remove redundant setting of AV_FRAME_FLAG_KEY, AV_PICTURE_TYPE_I 
This is done generically now.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-05-19 11:40:07 +02:00

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/*
* MagicYUV decoder
* Copyright (c) 2016 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 <stdlib.h>
#include <string.h>
#define CACHED_BITSTREAM_READER !ARCH_X86_32
#include "libavutil/mem.h"
#include "libavutil/pixdesc.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "decode.h"
#include "get_bits.h"
#include "lossless_videodsp.h"
#include "thread.h"
#define VLC_BITS 12
typedef struct Slice {
uint32_t start;
uint32_t size;
} Slice;
typedef enum Prediction {
LEFT = 1,
GRADIENT,
MEDIAN,
} Prediction;
typedef struct HuffEntry {
uint8_t len;
uint16_t sym;
} HuffEntry;
typedef struct MagicYUVContext {
AVFrame *p;
int max;
int bps;
int slice_height;
int nb_slices;
int planes; // number of encoded planes in bitstream
int decorrelate; // postprocessing work
int color_matrix; // video color matrix
int flags;
int interlaced; // video is interlaced
const uint8_t *buf; // pointer to AVPacket->data
int hshift[4];
int vshift[4];
Slice *slices[4]; // slice bitstream positions for each plane
unsigned int slices_size[4]; // slice sizes for each plane
VLC vlc[4]; // VLC for each plane
VLC_MULTI multi[4]; // Buffer for joint VLC data
int (*magy_decode_slice)(AVCodecContext *avctx, void *tdata,
int j, int threadnr);
LLVidDSPContext llviddsp;
HuffEntry he[1 << 14];
uint8_t len[1 << 14];
} MagicYUVContext;
static int huff_build(AVCodecContext *avctx,
const uint8_t len[], uint16_t codes_pos[33],
VLC *vlc, VLC_MULTI *multi, int nb_elems, void *logctx)
{
MagicYUVContext *s = avctx->priv_data;
HuffEntry *he = s->he;
for (int i = 31; i > 0; i--)
codes_pos[i] += codes_pos[i + 1];
for (unsigned i = nb_elems; i-- > 0;)
he[--codes_pos[len[i]]] = (HuffEntry){ len[i], i };
ff_vlc_free(vlc);
ff_vlc_free_multi(multi);
return ff_vlc_init_multi_from_lengths(vlc, multi, FFMIN(he[0].len, VLC_BITS), nb_elems, nb_elems,
&he[0].len, sizeof(he[0]),
&he[0].sym, sizeof(he[0]), sizeof(he[0].sym),
0, 0, logctx);
}
static void magicyuv_median_pred16(uint16_t *dst, const uint16_t *src1,
const uint16_t *diff, intptr_t w,
int *left, int *left_top, int max)
{
int i;
uint16_t l, lt;
l = *left;
lt = *left_top;
for (i = 0; i < w; i++) {
l = mid_pred(l, src1[i], (l + src1[i] - lt)) + diff[i];
l &= max;
lt = src1[i];
dst[i] = l;
}
*left = l;
*left_top = lt;
}
#define READ_PLANE(dst, plane, b, c) \
{ \
x = 0; \
for (; CACHED_BITSTREAM_READER && x < width-c && get_bits_left(&gb) > 0;) {\
ret = get_vlc_multi(&gb, (uint8_t *)dst + x * b, multi, \
vlc, vlc_bits, 3, b); \
if (ret <= 0) \
return AVERROR_INVALIDDATA; \
x += ret; \
} \
for (; x < width && get_bits_left(&gb) > 0; x++) \
dst[x] = get_vlc2(&gb, vlc, vlc_bits, 3); \
dst += stride; \
}
static int magy_decode_slice10(AVCodecContext *avctx, void *tdata,
int j, int threadnr)
{
const MagicYUVContext *s = avctx->priv_data;
int interlaced = s->interlaced;
const int bps = s->bps;
const int max = s->max - 1;
AVFrame *p = s->p;
int i, k, x;
GetBitContext gb;
uint16_t *dst;
for (i = 0; i < s->planes; i++) {
int left, lefttop, top;
int height = AV_CEIL_RSHIFT(FFMIN(s->slice_height, avctx->coded_height - j * s->slice_height), s->vshift[i]);
int width = AV_CEIL_RSHIFT(avctx->coded_width, s->hshift[i]);
int sheight = AV_CEIL_RSHIFT(s->slice_height, s->vshift[i]);
ptrdiff_t fake_stride = (p->linesize[i] / 2) * (1 + interlaced);
ptrdiff_t stride = p->linesize[i] / 2;
const VLC_MULTI_ELEM *const multi = s->multi[i].table;
const VLCElem *const vlc = s->vlc[i].table;
const int vlc_bits = s->vlc[i].bits;
int flags, pred;
int ret = init_get_bits8(&gb, s->buf + s->slices[i][j].start,
s->slices[i][j].size);
if (ret < 0)
return ret;
flags = get_bits(&gb, 8);
pred = get_bits(&gb, 8);
dst = (uint16_t *)p->data[i] + j * sheight * stride;
if (flags & 1) {
if (get_bits_left(&gb) < bps * width * height)
return AVERROR_INVALIDDATA;
for (k = 0; k < height; k++) {
for (x = 0; x < width; x++)
dst[x] = get_bits(&gb, bps);
dst += stride;
}
} else {
for (k = 0; k < height; k++)
READ_PLANE(dst, i, 2, 3)
}
switch (pred) {
case LEFT:
dst = (uint16_t *)p->data[i] + j * sheight * stride;
s->llviddsp.add_left_pred_int16(dst, dst, max, width, 0);
dst += stride;
if (interlaced) {
s->llviddsp.add_left_pred_int16(dst, dst, max, width, 0);
dst += stride;
}
for (k = 1 + interlaced; k < height; k++) {
s->llviddsp.add_left_pred_int16(dst, dst, max, width, dst[-fake_stride]);
dst += stride;
}
break;
case GRADIENT:
dst = (uint16_t *)p->data[i] + j * sheight * stride;
s->llviddsp.add_left_pred_int16(dst, dst, max, width, 0);
dst += stride;
if (interlaced) {
s->llviddsp.add_left_pred_int16(dst, dst, max, width, 0);
dst += stride;
}
for (k = 1 + interlaced; k < height; k++) {
top = dst[-fake_stride];
left = top + dst[0];
dst[0] = left & max;
for (x = 1; x < width; x++) {
top = dst[x - fake_stride];
lefttop = dst[x - (fake_stride + 1)];
left += top - lefttop + dst[x];
dst[x] = left & max;
}
dst += stride;
}
break;
case MEDIAN:
dst = (uint16_t *)p->data[i] + j * sheight * stride;
s->llviddsp.add_left_pred_int16(dst, dst, max, width, 0);
dst += stride;
if (interlaced) {
s->llviddsp.add_left_pred_int16(dst, dst, max, width, 0);
dst += stride;
}
lefttop = left = dst[0];
for (k = 1 + interlaced; k < height; k++) {
magicyuv_median_pred16(dst, dst - fake_stride, dst, width, &left, &lefttop, max);
lefttop = left = dst[0];
dst += stride;
}
break;
default:
avpriv_request_sample(avctx, "Unknown prediction: %d", pred);
}
}
if (s->decorrelate) {
int height = FFMIN(s->slice_height, avctx->coded_height - j * s->slice_height);
int width = avctx->coded_width;
uint16_t *r = (uint16_t *)p->data[0] + j * s->slice_height * p->linesize[0] / 2;
uint16_t *g = (uint16_t *)p->data[1] + j * s->slice_height * p->linesize[1] / 2;
uint16_t *b = (uint16_t *)p->data[2] + j * s->slice_height * p->linesize[2] / 2;
for (i = 0; i < height; i++) {
for (k = 0; k < width; k++) {
b[k] = (b[k] + g[k]) & max;
r[k] = (r[k] + g[k]) & max;
}
b += p->linesize[0] / 2;
g += p->linesize[1] / 2;
r += p->linesize[2] / 2;
}
}
return 0;
}
static int magy_decode_slice(AVCodecContext *avctx, void *tdata,
int j, int threadnr)
{
const MagicYUVContext *s = avctx->priv_data;
int interlaced = s->interlaced;
AVFrame *p = s->p;
int i, k, x, min_width;
GetBitContext gb;
uint8_t *dst;
for (i = 0; i < s->planes; i++) {
int left, lefttop, top;
int height = AV_CEIL_RSHIFT(FFMIN(s->slice_height, avctx->coded_height - j * s->slice_height), s->vshift[i]);
int width = AV_CEIL_RSHIFT(avctx->coded_width, s->hshift[i]);
int sheight = AV_CEIL_RSHIFT(s->slice_height, s->vshift[i]);
ptrdiff_t fake_stride = p->linesize[i] * (1 + interlaced);
ptrdiff_t stride = p->linesize[i];
const uint8_t *slice = s->buf + s->slices[i][j].start;
const VLC_MULTI_ELEM *const multi = s->multi[i].table;
const VLCElem *const vlc = s->vlc[i].table;
const int vlc_bits = s->vlc[i].bits;
int flags, pred;
flags = bytestream_get_byte(&slice);
pred = bytestream_get_byte(&slice);
dst = p->data[i] + j * sheight * stride;
if (flags & 1) {
if (s->slices[i][j].size - 2 < width * height)
return AVERROR_INVALIDDATA;
for (k = 0; k < height; k++) {
bytestream_get_buffer(&slice, dst, width);
dst += stride;
}
} else {
int ret = init_get_bits8(&gb, slice, s->slices[i][j].size - 2);
if (ret < 0)
return ret;
for (k = 0; k < height; k++)
READ_PLANE(dst, i, 1, 7)
}
switch (pred) {
case LEFT:
dst = p->data[i] + j * sheight * stride;
s->llviddsp.add_left_pred(dst, dst, width, 0);
dst += stride;
if (interlaced) {
s->llviddsp.add_left_pred(dst, dst, width, 0);
dst += stride;
}
for (k = 1 + interlaced; k < height; k++) {
s->llviddsp.add_left_pred(dst, dst, width, dst[-fake_stride]);
dst += stride;
}
break;
case GRADIENT:
dst = p->data[i] + j * sheight * stride;
s->llviddsp.add_left_pred(dst, dst, width, 0);
dst += stride;
if (interlaced) {
s->llviddsp.add_left_pred(dst, dst, width, 0);
dst += stride;
}
min_width = FFMIN(width, 32);
for (k = 1 + interlaced; k < height; k++) {
top = dst[-fake_stride];
left = top + dst[0];
dst[0] = left;
for (x = 1; x < min_width; x++) { /* dsp need aligned 32 */
top = dst[x - fake_stride];
lefttop = dst[x - (fake_stride + 1)];
left += top - lefttop + dst[x];
dst[x] = left;
}
if (width > 32)
s->llviddsp.add_gradient_pred(dst + 32, fake_stride, width - 32);
dst += stride;
}
break;
case MEDIAN:
dst = p->data[i] + j * sheight * stride;
s->llviddsp.add_left_pred(dst, dst, width, 0);
dst += stride;
if (interlaced) {
s->llviddsp.add_left_pred(dst, dst, width, 0);
dst += stride;
}
lefttop = left = dst[0];
for (k = 1 + interlaced; k < height; k++) {
s->llviddsp.add_median_pred(dst, dst - fake_stride,
dst, width, &left, &lefttop);
lefttop = left = dst[0];
dst += stride;
}
break;
default:
avpriv_request_sample(avctx, "Unknown prediction: %d", pred);
}
}
if (s->decorrelate) {
int height = FFMIN(s->slice_height, avctx->coded_height - j * s->slice_height);
int width = avctx->coded_width;
uint8_t *b = p->data[0] + j * s->slice_height * p->linesize[0];
uint8_t *g = p->data[1] + j * s->slice_height * p->linesize[1];
uint8_t *r = p->data[2] + j * s->slice_height * p->linesize[2];
for (i = 0; i < height; i++) {
s->llviddsp.add_bytes(b, g, width);
s->llviddsp.add_bytes(r, g, width);
b += p->linesize[0];
g += p->linesize[1];
r += p->linesize[2];
}
}
return 0;
}
static int build_huffman(AVCodecContext *avctx, const uint8_t *table,
int table_size, int max)
{
MagicYUVContext *s = avctx->priv_data;
GetByteContext gb;
uint8_t *len = s->len;
uint16_t length_count[33] = { 0 };
int i = 0, j = 0, k;
bytestream2_init(&gb, table, table_size);
while (bytestream2_get_bytes_left(&gb) > 0) {
int b = bytestream2_peek_byteu(&gb) & 0x80;
int x = bytestream2_get_byteu(&gb) & ~0x80;
int l = 1;
if (b) {
if (bytestream2_get_bytes_left(&gb) <= 0)
break;
l += bytestream2_get_byteu(&gb);
}
k = j + l;
if (k > max || x == 0 || x > 32) {
av_log(avctx, AV_LOG_ERROR, "Invalid Huffman codes\n");
return AVERROR_INVALIDDATA;
}
length_count[x] += l;
for (; j < k; j++)
len[j] = x;
if (j == max) {
j = 0;
if (huff_build(avctx, len, length_count, &s->vlc[i], &s->multi[i], max, avctx)) {
av_log(avctx, AV_LOG_ERROR, "Cannot build Huffman codes\n");
return AVERROR_INVALIDDATA;
}
i++;
if (i == s->planes) {
break;
}
memset(length_count, 0, sizeof(length_count));
}
}
if (i != s->planes) {
av_log(avctx, AV_LOG_ERROR, "Huffman tables too short\n");
return AVERROR_INVALIDDATA;
}
return 0;
}
static int magy_decode_frame(AVCodecContext *avctx, AVFrame *p,
int *got_frame, AVPacket *avpkt)
{
MagicYUVContext *s = avctx->priv_data;
GetByteContext gb;
uint32_t first_offset, offset, next_offset, header_size, slice_width;
int width, height, format, version, table_size;
int ret, i, j;
if (avpkt->size < 36)
return AVERROR_INVALIDDATA;
bytestream2_init(&gb, avpkt->data, avpkt->size);
if (bytestream2_get_le32u(&gb) != MKTAG('M', 'A', 'G', 'Y'))
return AVERROR_INVALIDDATA;
header_size = bytestream2_get_le32u(&gb);
if (header_size < 32 || header_size >= avpkt->size) {
av_log(avctx, AV_LOG_ERROR,
"header or packet too small %"PRIu32"\n", header_size);
return AVERROR_INVALIDDATA;
}
version = bytestream2_get_byteu(&gb);
if (version != 7) {
avpriv_request_sample(avctx, "Version %d", version);
return AVERROR_PATCHWELCOME;
}
s->hshift[1] =
s->vshift[1] =
s->hshift[2] =
s->vshift[2] = 0;
s->decorrelate = 0;
s->bps = 8;
format = bytestream2_get_byteu(&gb);
switch (format) {
case 0x65:
avctx->pix_fmt = AV_PIX_FMT_GBRP;
s->decorrelate = 1;
break;
case 0x66:
avctx->pix_fmt = AV_PIX_FMT_GBRAP;
s->decorrelate = 1;
break;
case 0x67:
avctx->pix_fmt = AV_PIX_FMT_YUV444P;
break;
case 0x68:
avctx->pix_fmt = AV_PIX_FMT_YUV422P;
s->hshift[1] =
s->hshift[2] = 1;
break;
case 0x69:
avctx->pix_fmt = AV_PIX_FMT_YUV420P;
s->hshift[1] =
s->vshift[1] =
s->hshift[2] =
s->vshift[2] = 1;
break;
case 0x6a:
avctx->pix_fmt = AV_PIX_FMT_YUVA444P;
break;
case 0x6b:
avctx->pix_fmt = AV_PIX_FMT_GRAY8;
break;
case 0x6c:
avctx->pix_fmt = AV_PIX_FMT_YUV422P10;
s->hshift[1] =
s->hshift[2] = 1;
s->bps = 10;
break;
case 0x76:
avctx->pix_fmt = AV_PIX_FMT_YUV444P10;
s->bps = 10;
break;
case 0x6d:
avctx->pix_fmt = AV_PIX_FMT_GBRP10;
s->decorrelate = 1;
s->bps = 10;
break;
case 0x6e:
avctx->pix_fmt = AV_PIX_FMT_GBRAP10;
s->decorrelate = 1;
s->bps = 10;
break;
case 0x6f:
avctx->pix_fmt = AV_PIX_FMT_GBRP12;
s->decorrelate = 1;
s->bps = 12;
break;
case 0x70:
avctx->pix_fmt = AV_PIX_FMT_GBRAP12;
s->decorrelate = 1;
s->bps = 12;
break;
case 0x71:
avctx->pix_fmt = AV_PIX_FMT_GBRP14;
s->decorrelate = 1;
s->bps = 14;
break;
case 0x72:
avctx->pix_fmt = AV_PIX_FMT_GBRAP14;
s->decorrelate = 1;
s->bps = 14;
break;
case 0x73:
avctx->pix_fmt = AV_PIX_FMT_GRAY10;
s->bps = 10;
break;
case 0x7b:
avctx->pix_fmt = AV_PIX_FMT_YUV420P10;
s->hshift[1] =
s->vshift[1] =
s->hshift[2] =
s->vshift[2] = 1;
s->bps = 10;
break;
default:
avpriv_request_sample(avctx, "Format 0x%X", format);
return AVERROR_PATCHWELCOME;
}
s->max = 1 << s->bps;
s->magy_decode_slice = s->bps == 8 ? magy_decode_slice : magy_decode_slice10;
s->planes = av_pix_fmt_count_planes(avctx->pix_fmt);
bytestream2_skipu(&gb, 1);
s->color_matrix = bytestream2_get_byteu(&gb);
s->flags = bytestream2_get_byteu(&gb);
s->interlaced = !!(s->flags & 2);
bytestream2_skipu(&gb, 3);
width = bytestream2_get_le32u(&gb);
height = bytestream2_get_le32u(&gb);
ret = ff_set_dimensions(avctx, width, height);
if (ret < 0)
return ret;
slice_width = bytestream2_get_le32u(&gb);
if (slice_width != avctx->coded_width) {
avpriv_request_sample(avctx, "Slice width %"PRIu32, slice_width);
return AVERROR_PATCHWELCOME;
}
s->slice_height = bytestream2_get_le32u(&gb);
if (s->slice_height <= 0 || s->slice_height > INT_MAX - avctx->coded_height) {
av_log(avctx, AV_LOG_ERROR,
"invalid slice height: %d\n", s->slice_height);
return AVERROR_INVALIDDATA;
}
bytestream2_skipu(&gb, 4);
s->nb_slices = (avctx->coded_height + s->slice_height - 1) / s->slice_height;
if (s->nb_slices > INT_MAX / FFMAX(sizeof(Slice), 4 * 5)) {
av_log(avctx, AV_LOG_ERROR,
"invalid number of slices: %d\n", s->nb_slices);
return AVERROR_INVALIDDATA;
}
if (s->interlaced) {
if ((s->slice_height >> s->vshift[1]) < 2) {
av_log(avctx, AV_LOG_ERROR, "impossible slice height\n");
return AVERROR_INVALIDDATA;
}
if ((avctx->coded_height % s->slice_height) && ((avctx->coded_height % s->slice_height) >> s->vshift[1]) < 2) {
av_log(avctx, AV_LOG_ERROR, "impossible height\n");
return AVERROR_INVALIDDATA;
}
}
if (bytestream2_get_bytes_left(&gb) <= s->nb_slices * s->planes * 5)
return AVERROR_INVALIDDATA;
for (i = 0; i < s->planes; i++) {
av_fast_malloc(&s->slices[i], &s->slices_size[i], s->nb_slices * sizeof(Slice));
if (!s->slices[i])
return AVERROR(ENOMEM);
offset = bytestream2_get_le32u(&gb);
if (offset >= avpkt->size - header_size)
return AVERROR_INVALIDDATA;
if (i == 0)
first_offset = offset;
for (j = 0; j < s->nb_slices - 1; j++) {
s->slices[i][j].start = offset + header_size;
next_offset = bytestream2_get_le32u(&gb);
if (next_offset <= offset || next_offset >= avpkt->size - header_size)
return AVERROR_INVALIDDATA;
s->slices[i][j].size = next_offset - offset;
if (s->slices[i][j].size < 2)
return AVERROR_INVALIDDATA;
offset = next_offset;
}
s->slices[i][j].start = offset + header_size;
s->slices[i][j].size = avpkt->size - s->slices[i][j].start;
if (s->slices[i][j].size < 2)
return AVERROR_INVALIDDATA;
}
if (bytestream2_get_byteu(&gb) != s->planes)
return AVERROR_INVALIDDATA;
bytestream2_skipu(&gb, s->nb_slices * s->planes);
table_size = header_size + first_offset - bytestream2_tell(&gb);
if (table_size < 2)
return AVERROR_INVALIDDATA;
ret = build_huffman(avctx, avpkt->data + bytestream2_tell(&gb),
table_size, s->max);
if (ret < 0)
return ret;
if ((ret = ff_thread_get_buffer(avctx, p, 0)) < 0)
return ret;
s->buf = avpkt->data;
s->p = p;
avctx->execute2(avctx, s->magy_decode_slice, NULL, NULL, s->nb_slices);
if (avctx->pix_fmt == AV_PIX_FMT_GBRP ||
avctx->pix_fmt == AV_PIX_FMT_GBRAP ||
avctx->pix_fmt == AV_PIX_FMT_GBRP10 ||
avctx->pix_fmt == AV_PIX_FMT_GBRAP10||
avctx->pix_fmt == AV_PIX_FMT_GBRAP12||
avctx->pix_fmt == AV_PIX_FMT_GBRAP14||
avctx->pix_fmt == AV_PIX_FMT_GBRP12||
avctx->pix_fmt == AV_PIX_FMT_GBRP14) {
FFSWAP(uint8_t*, p->data[0], p->data[1]);
FFSWAP(int, p->linesize[0], p->linesize[1]);
} else {
switch (s->color_matrix) {
case 1:
p->colorspace = AVCOL_SPC_BT470BG;
break;
case 2:
p->colorspace = AVCOL_SPC_BT709;
break;
}
p->color_range = (s->flags & 4) ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
}
*got_frame = 1;
return avpkt->size;
}
static av_cold int magy_decode_init(AVCodecContext *avctx)
{
MagicYUVContext *s = avctx->priv_data;
ff_llviddsp_init(&s->llviddsp);
return 0;
}
static av_cold int magy_decode_end(AVCodecContext *avctx)
{
MagicYUVContext * const s = avctx->priv_data;
int i;
for (i = 0; i < FF_ARRAY_ELEMS(s->slices); i++) {
av_freep(&s->slices[i]);
s->slices_size[i] = 0;
ff_vlc_free(&s->vlc[i]);
ff_vlc_free_multi(&s->multi[i]);
}
return 0;
}
const FFCodec ff_magicyuv_decoder = {
.p.name = "magicyuv",
CODEC_LONG_NAME("MagicYUV video"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_MAGICYUV,
.priv_data_size = sizeof(MagicYUVContext),
.init = magy_decode_init,
.close = magy_decode_end,
FF_CODEC_DECODE_CB(magy_decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1 |
AV_CODEC_CAP_FRAME_THREADS |
AV_CODEC_CAP_SLICE_THREADS,
};
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