virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-28 20:53:54 +02:00
Code Issues Releases Activity
fa26e17747
FFmpeg/libavcodec/cinepak.c
Andreas Rheinhardt 4243da4ff4 avcodec/codec_internal: Use union for FFCodec decode/encode callbacks 
This is possible, because every given FFCodec has to implement
exactly one of these. Doing so decreases sizeof(FFCodec) and
therefore decreases the size of the binary.
Notice that in case of position-independent code the decrease
is in .data.rel.ro, so that this translates to decreased
memory consumption.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-04-05 20:02:37 +02:00

521 lines
16 KiB
C
Raw Blame History

/*
* Cinepak Video Decoder
* Copyright (C) 2003 The FFmpeg project
*
* 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
* Cinepak video decoder
* @author Ewald Snel <ewald@rambo.its.tudelft.nl>
*
* @see For more information on the Cinepak algorithm, visit:
* http://www.csse.monash.edu.au/~timf/
* @see For more information on the quirky data inside Sega FILM/CPK files, visit:
* http://wiki.multimedia.cx/index.php?title=Sega_FILM
*
* Cinepak colorspace support (c) 2013 Rl, Aetey Global Technologies AB
* @author Cinepak colorspace, Rl, Aetey Global Technologies AB
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
#include "internal.h"
typedef uint8_t cvid_codebook[12];
#define MAX_STRIPS 32
typedef struct cvid_strip {
uint16_t id;
uint16_t x1, y1;
uint16_t x2, y2;
cvid_codebook v4_codebook[256];
cvid_codebook v1_codebook[256];
} cvid_strip;
typedef struct CinepakContext {
AVCodecContext *avctx;
AVFrame *frame;
const unsigned char *data;
int size;
int width, height;
int palette_video;
cvid_strip strips[MAX_STRIPS];
int sega_film_skip_bytes;
uint32_t pal[256];
} CinepakContext;
static void cinepak_decode_codebook (cvid_codebook *codebook,
int chunk_id, int size, const uint8_t *data)
{
const uint8_t *eod = (data + size);
uint32_t flag, mask;
int i, n;
uint8_t *p;
/* check if this chunk contains 4- or 6-element vectors */
n = (chunk_id & 0x04) ? 4 : 6;
flag = 0;
mask = 0;
p = codebook[0];
for (i=0; i < 256; i++) {
if ((chunk_id & 0x01) && !(mask >>= 1)) {
if ((data + 4) > eod)
break;
flag = AV_RB32 (data);
data += 4;
mask = 0x80000000;
}
if (!(chunk_id & 0x01) || (flag & mask)) {
int k, kk;
if ((data + n) > eod)
break;
for (k = 0; k < 4; ++k) {
int r = *data++;
for (kk = 0; kk < 3; ++kk)
*p++ = r;
}
if (n == 6) {
int r, g, b, u, v;
u = *(int8_t *)data++;
v = *(int8_t *)data++;
p -= 12;
for(k=0; k<4; ++k) {
r = *p++ + v*2;
g = *p++ - (u/2) - v;
b = *p + u*2;
p -= 2;
*p++ = av_clip_uint8(r);
*p++ = av_clip_uint8(g);
*p++ = av_clip_uint8(b);
}
}
} else {
p += 12;
}
}
}
static int cinepak_decode_vectors (CinepakContext *s, cvid_strip *strip,
int chunk_id, int size, const uint8_t *data)
{
const uint8_t *eod = (data + size);
uint32_t flag, mask;
uint8_t *cb0, *cb1, *cb2, *cb3;
int x, y;
char *ip0, *ip1, *ip2, *ip3;
flag = 0;
mask = 0;
for (y=strip->y1; y < strip->y2; y+=4) {
/* take care of y dimension not being multiple of 4, such streams exist */
ip0 = ip1 = ip2 = ip3 = s->frame->data[0] +
(s->palette_video?strip->x1:strip->x1*3) + (y * s->frame->linesize[0]);
if(s->avctx->height - y > 1) {
ip1 = ip0 + s->frame->linesize[0];
if(s->avctx->height - y > 2) {
ip2 = ip1 + s->frame->linesize[0];
if(s->avctx->height - y > 3) {
ip3 = ip2 + s->frame->linesize[0];
}
}
}
/* to get the correct picture for not-multiple-of-4 cases let us fill each
* block from the bottom up, thus possibly overwriting the bottommost line
* more than once but ending with the correct data in place
* (instead of in-loop checking) */
for (x=strip->x1; x < strip->x2; x+=4) {
if ((chunk_id & 0x01) && !(mask >>= 1)) {
if ((data + 4) > eod)
return AVERROR_INVALIDDATA;
flag = AV_RB32 (data);
data += 4;
mask = 0x80000000;
}
if (!(chunk_id & 0x01) || (flag & mask)) {
if (!(chunk_id & 0x02) && !(mask >>= 1)) {
if ((data + 4) > eod)
return AVERROR_INVALIDDATA;
flag = AV_RB32 (data);
data += 4;
mask = 0x80000000;
}
if ((chunk_id & 0x02) || (~flag & mask)) {
uint8_t *p;
if (data >= eod)
return AVERROR_INVALIDDATA;
p = strip->v1_codebook[*data++];
if (s->palette_video) {
ip3[0] = ip3[1] = ip2[0] = ip2[1] = p[6];
ip3[2] = ip3[3] = ip2[2] = ip2[3] = p[9];
ip1[0] = ip1[1] = ip0[0] = ip0[1] = p[0];
ip1[2] = ip1[3] = ip0[2] = ip0[3] = p[3];
} else {
p += 6;
memcpy(ip3 + 0, p, 3); memcpy(ip3 + 3, p, 3);
memcpy(ip2 + 0, p, 3); memcpy(ip2 + 3, p, 3);
p += 3; /* ... + 9 */
memcpy(ip3 + 6, p, 3); memcpy(ip3 + 9, p, 3);
memcpy(ip2 + 6, p, 3); memcpy(ip2 + 9, p, 3);
p -= 9; /* ... + 0 */
memcpy(ip1 + 0, p, 3); memcpy(ip1 + 3, p, 3);
memcpy(ip0 + 0, p, 3); memcpy(ip0 + 3, p, 3);
p += 3; /* ... + 3 */
memcpy(ip1 + 6, p, 3); memcpy(ip1 + 9, p, 3);
memcpy(ip0 + 6, p, 3); memcpy(ip0 + 9, p, 3);
}
} else if (flag & mask) {
if ((data + 4) > eod)
return AVERROR_INVALIDDATA;
cb0 = strip->v4_codebook[*data++];
cb1 = strip->v4_codebook[*data++];
cb2 = strip->v4_codebook[*data++];
cb3 = strip->v4_codebook[*data++];
if (s->palette_video) {
uint8_t *p;
p = ip3;
*p++ = cb2[6];
*p++ = cb2[9];
*p++ = cb3[6];
*p = cb3[9];
p = ip2;
*p++ = cb2[0];
*p++ = cb2[3];
*p++ = cb3[0];
*p = cb3[3];
p = ip1;
*p++ = cb0[6];
*p++ = cb0[9];
*p++ = cb1[6];
*p = cb1[9];
p = ip0;
*p++ = cb0[0];
*p++ = cb0[3];
*p++ = cb1[0];
*p = cb1[3];
} else {
memcpy(ip3 + 0, cb2 + 6, 6);
memcpy(ip3 + 6, cb3 + 6, 6);
memcpy(ip2 + 0, cb2 + 0, 6);
memcpy(ip2 + 6, cb3 + 0, 6);
memcpy(ip1 + 0, cb0 + 6, 6);
memcpy(ip1 + 6, cb1 + 6, 6);
memcpy(ip0 + 0, cb0 + 0, 6);
memcpy(ip0 + 6, cb1 + 0, 6);
}
}
}
if (s->palette_video) {
ip0 += 4; ip1 += 4;
ip2 += 4; ip3 += 4;
} else {
ip0 += 12; ip1 += 12;
ip2 += 12; ip3 += 12;
}
}
}
return 0;
}
static int cinepak_decode_strip (CinepakContext *s,
cvid_strip *strip, const uint8_t *data, int size)
{
const uint8_t *eod = (data + size);
int chunk_id, chunk_size;
/* coordinate sanity checks */
if (strip->x2 > s->width ||
strip->y2 > s->height ||
strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
return AVERROR_INVALIDDATA;
while ((data + 4) <= eod) {
chunk_id = data[0];
chunk_size = AV_RB24 (&data[1]) - 4;
if(chunk_size < 0)
return AVERROR_INVALIDDATA;
data += 4;
chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
switch (chunk_id) {
case 0x20:
case 0x21:
case 0x24:
case 0x25:
cinepak_decode_codebook (strip->v4_codebook, chunk_id,
chunk_size, data);
break;
case 0x22:
case 0x23:
case 0x26:
case 0x27:
cinepak_decode_codebook (strip->v1_codebook, chunk_id,
chunk_size, data);
break;
case 0x30:
case 0x31:
case 0x32:
return cinepak_decode_vectors (s, strip, chunk_id,
chunk_size, data);
}
data += chunk_size;
}
return AVERROR_INVALIDDATA;
}
static int cinepak_predecode_check (CinepakContext *s)
{
int num_strips;
int encoded_buf_size;
num_strips = AV_RB16 (&s->data[8]);
encoded_buf_size = AV_RB24(&s->data[1]);
if (s->size < encoded_buf_size * (int64_t)(100 - s->avctx->discard_damaged_percentage) / 100)
return AVERROR_INVALIDDATA;
/* if this is the first frame, check for deviant Sega FILM data */
if (s->sega_film_skip_bytes == -1) {
if (!encoded_buf_size) {
avpriv_request_sample(s->avctx, "encoded_buf_size 0");
return AVERROR_PATCHWELCOME;
}
if (encoded_buf_size != s->size && (s->size % encoded_buf_size) != 0) {
/* If the encoded frame size differs from the frame size as indicated
* by the container file, this data likely comes from a Sega FILM/CPK file.
* If the frame header is followed by the bytes FE 00 00 06 00 00 then
* this is probably one of the two known files that have 6 extra bytes
* after the frame header. Else, assume 2 extra bytes. The container
* size also cannot be a multiple of the encoded size. */
if (s->size >= 16 &&
(s->data[10] == 0xFE) &&
(s->data[11] == 0x00) &&
(s->data[12] == 0x00) &&
(s->data[13] == 0x06) &&
(s->data[14] == 0x00) &&
(s->data[15] == 0x00))
s->sega_film_skip_bytes = 6;
else
s->sega_film_skip_bytes = 2;
} else
s->sega_film_skip_bytes = 0;
}
if (s->size < 10 + s->sega_film_skip_bytes + num_strips * 12)
return AVERROR_INVALIDDATA;
if (num_strips) {
const uint8_t *data = s->data + 10 + s->sega_film_skip_bytes;
int strip_size = AV_RB24 (data + 1);
if (strip_size < 12 || strip_size > encoded_buf_size)
return AVERROR_INVALIDDATA;
}
return 0;
}
static int cinepak_decode (CinepakContext *s)
{
const uint8_t *eod = (s->data + s->size);
int i, result, strip_size, frame_flags, num_strips;
int y0 = 0;
frame_flags = s->data[0];
num_strips = AV_RB16 (&s->data[8]);
s->data += 10 + s->sega_film_skip_bytes;
num_strips = FFMIN(num_strips, MAX_STRIPS);
s->frame->key_frame = 0;
for (i=0; i < num_strips; i++) {
if ((s->data + 12) > eod)
return AVERROR_INVALIDDATA;
s->strips[i].id = s->data[0];
/* zero y1 means "relative to the previous stripe" */
if (!(s->strips[i].y1 = AV_RB16 (&s->data[4])))
s->strips[i].y2 = (s->strips[i].y1 = y0) + AV_RB16 (&s->data[8]);
else
s->strips[i].y2 = AV_RB16 (&s->data[8]);
s->strips[i].x1 = AV_RB16 (&s->data[6]);
s->strips[i].x2 = AV_RB16 (&s->data[10]);
if (s->strips[i].id == 0x10)
s->frame->key_frame = 1;
strip_size = AV_RB24 (&s->data[1]) - 12;
if (strip_size < 0)
return AVERROR_INVALIDDATA;
s->data += 12;
strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
if ((i > 0) && !(frame_flags & 0x01)) {
memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
sizeof(s->strips[i].v4_codebook));
memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
sizeof(s->strips[i].v1_codebook));
}
result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
if (result != 0)
return result;
s->data += strip_size;
y0 = s->strips[i].y2;
}
return 0;
}
static av_cold int cinepak_decode_init(AVCodecContext *avctx)
{
CinepakContext *s = avctx->priv_data;
s->avctx = avctx;
s->width = (avctx->width + 3) & ~3;
s->height = (avctx->height + 3) & ~3;
s->sega_film_skip_bytes = -1; /* uninitialized state */
// check for paletted data
if (avctx->bits_per_coded_sample != 8) {
s->palette_video = 0;
avctx->pix_fmt = AV_PIX_FMT_RGB24;
} else {
s->palette_video = 1;
avctx->pix_fmt = AV_PIX_FMT_PAL8;
}
s->frame = av_frame_alloc();
if (!s->frame)
return AVERROR(ENOMEM);
return 0;
}
static int cinepak_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int ret = 0, buf_size = avpkt->size;
CinepakContext *s = avctx->priv_data;
int num_strips;
s->data = buf;
s->size = buf_size;
if (s->size < 10)
return AVERROR_INVALIDDATA;
num_strips = AV_RB16 (&s->data[8]);
//Empty frame, do not waste time
if (!num_strips && (!s->palette_video || !av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL)))
return buf_size;
if ((ret = cinepak_predecode_check(s)) < 0) {
av_log(avctx, AV_LOG_ERROR, "cinepak_predecode_check failed\n");
return ret;
}
if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
return ret;
if (s->palette_video) {
s->frame->palette_has_changed = ff_copy_palette(s->pal, avpkt, avctx);
}
if ((ret = cinepak_decode(s)) < 0) {
av_log(avctx, AV_LOG_ERROR, "cinepak_decode failed\n");
}
if (s->palette_video)
memcpy (s->frame->data[1], s->pal, AVPALETTE_SIZE);
if ((ret = av_frame_ref(rframe, s->frame)) < 0)
return ret;
*got_frame = 1;
/* report that the buffer was completely consumed */
return buf_size;
}
static av_cold int cinepak_decode_end(AVCodecContext *avctx)
{
CinepakContext *s = avctx->priv_data;
av_frame_free(&s->frame);
return 0;
}
const FFCodec ff_cinepak_decoder = {
.p.name = "cinepak",
.p.long_name = NULL_IF_CONFIG_SMALL("Cinepak"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_CINEPAK,
.priv_data_size = sizeof(CinepakContext),
.init = cinepak_decode_init,
.close = cinepak_decode_end,
FF_CODEC_DECODE_CB(cinepak_decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
Reference in New Issue View Git Blame Copy Permalink