1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-07 11:13:41 +02:00
FFmpeg/libavcodec/mimic.c
Stefano Sabatini 72415b2adb Define AVMediaType enum, and use it instead of enum CodecType, which
is deprecated and will be dropped at the next major bump.

Originally committed as revision 22735 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-03-30 23:30:55 +00:00

393 lines
14 KiB
C

/*
* Copyright (C) 2005 Ole André Vadla Ravnås <oleavr@gmail.com>
* Copyright (C) 2008 Ramiro Polla <ramiro@lisha.ufsc.br>
*
* 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>
#include <stdint.h>
#include "avcodec.h"
#include "get_bits.h"
#include "bytestream.h"
#include "dsputil.h"
#define MIMIC_HEADER_SIZE 20
typedef struct {
AVCodecContext *avctx;
int num_vblocks[3];
int num_hblocks[3];
void *swap_buf;
int swap_buf_size;
int cur_index;
int prev_index;
AVFrame buf_ptrs [16];
AVPicture flipped_ptrs[16];
DECLARE_ALIGNED(16, DCTELEM, dct_block)[64];
GetBitContext gb;
ScanTable scantable;
DSPContext dsp;
VLC vlc;
} MimicContext;
static const uint32_t huffcodes[] = {
0x0000000a, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x0000000b,
0x0000001b, 0x00000038, 0x00000078, 0x00000079, 0x0000007a, 0x000000f9,
0x000000fa, 0x000003fb, 0x000007f8, 0x000007f9, 0x000007fa, 0x000007fb,
0x00000ff8, 0x00000ff9, 0x00000001, 0x00000039, 0x0000007b, 0x000000fb,
0x000001f8, 0x000001f9, 0x00000ffa, 0x00000ffb, 0x00001ff8, 0x00001ff9,
0x00001ffa, 0x00001ffb, 0x00003ff8, 0x00003ff9, 0x00003ffa, 0x00000000,
0x00000004, 0x0000003a, 0x000001fa, 0x00003ffb, 0x00007ff8, 0x00007ff9,
0x00007ffa, 0x00007ffb, 0x0000fff8, 0x0000fff9, 0x0000fffa, 0x0000fffb,
0x0001fff8, 0x0001fff9, 0x0001fffa, 0x00000000, 0x0000000c, 0x000000f8,
0x000001fb, 0x0001fffb, 0x0003fff8, 0x0003fff9, 0x0003fffa, 0x0003fffb,
0x0007fff8, 0x0007fff9, 0x0007fffa, 0x0007fffb, 0x000ffff8, 0x000ffff9,
0x000ffffa, 0x00000000, 0x0000001a, 0x000003f8, 0x000ffffb, 0x001ffff8,
0x001ffff9, 0x001ffffa, 0x001ffffb, 0x003ffff8, 0x003ffff9, 0x003ffffa,
0x003ffffb, 0x007ffff8, 0x007ffff9, 0x007ffffa, 0x007ffffb, 0x00000000,
0x0000003b, 0x000003f9, 0x00fffff8, 0x00fffff9, 0x00fffffa, 0x00fffffb,
0x01fffff8, 0x01fffff9, 0x01fffffa, 0x01fffffb, 0x03fffff8, 0x03fffff9,
0x03fffffa, 0x03fffffb, 0x07fffff8, 0x00000000, 0x000003fa, 0x07fffff9,
0x07fffffa, 0x07fffffb, 0x0ffffff8, 0x0ffffff9, 0x0ffffffa, 0x0ffffffb,
0x1ffffff8, 0x1ffffff9, 0x1ffffffa, 0x1ffffffb, 0x3ffffff8, 0x3ffffff9,
0x3ffffffa,
};
static const uint8_t huffbits[] = {
4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 2, 4, 5, 6, 7, 7, 7, 8,
8, 10, 11, 11, 11, 11, 12, 12, 2, 6, 7, 8,
9, 9, 12, 12, 13, 13, 13, 13, 14, 14, 14, 0,
3, 6, 9, 14, 15, 15, 15, 15, 16, 16, 16, 16,
17, 17, 17, 0, 4, 8, 9, 17, 18, 18, 18, 18,
19, 19, 19, 19, 20, 20, 20, 0, 5, 10, 20, 21,
21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 0,
6, 10, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
26, 26, 27, 0, 10, 27, 27, 27, 28, 28, 28, 28,
29, 29, 29, 29, 30, 30, 30,
};
static const uint8_t col_zag[64] = {
0, 8, 1, 2, 9, 16, 24, 17,
10, 3, 4, 11, 18, 25, 32, 40,
33, 26, 19, 12, 5, 6, 13, 20,
27, 34, 41, 48, 56, 49, 42, 35,
28, 21, 14, 7, 15, 22, 29, 36,
43, 50, 57, 58, 51, 44, 37, 30,
23, 31, 38, 45, 52, 59, 39, 46,
53, 60, 61, 54, 47, 55, 62, 63,
};
static av_cold int mimic_decode_init(AVCodecContext *avctx)
{
MimicContext *ctx = avctx->priv_data;
ctx->prev_index = 0;
ctx->cur_index = 15;
if(init_vlc(&ctx->vlc, 11, FF_ARRAY_ELEMS(huffbits),
huffbits, 1, 1, huffcodes, 4, 4, 0)) {
av_log(avctx, AV_LOG_ERROR, "error initializing vlc table\n");
return -1;
}
dsputil_init(&ctx->dsp, avctx);
ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable, col_zag);
return 0;
}
static const int8_t vlcdec_lookup[9][64] = {
{ 0, },
{ -1, 1, },
{ -3, 3, -2, 2, },
{ -7, 7, -6, 6, -5, 5, -4, 4, },
{ -15, 15, -14, 14, -13, 13, -12, 12,
-11, 11, -10, 10, -9, 9, -8, 8, },
{ -31, 31, -30, 30, -29, 29, -28, 28,
-27, 27, -26, 26, -25, 25, -24, 24,
-23, 23, -22, 22, -21, 21, -20, 20,
-19, 19, -18, 18, -17, 17, -16, 16, },
{ -63, 63, -62, 62, -61, 61, -60, 60,
-59, 59, -58, 58, -57, 57, -56, 56,
-55, 55, -54, 54, -53, 53, -52, 52,
-51, 51, -50, 50, -49, 49, -48, 48,
-47, 47, -46, 46, -45, 45, -44, 44,
-43, 43, -42, 42, -41, 41, -40, 40,
-39, 39, -38, 38, -37, 37, -36, 36,
-35, 35, -34, 34, -33, 33, -32, 32, },
{ -127, 127, -126, 126, -125, 125, -124, 124,
-123, 123, -122, 122, -121, 121, -120, 120,
-119, 119, -118, 118, -117, 117, -116, 116,
-115, 115, -114, 114, -113, 113, -112, 112,
-111, 111, -110, 110, -109, 109, -108, 108,
-107, 107, -106, 106, -105, 105, -104, 104,
-103, 103, -102, 102, -101, 101, -100, 100,
-99, 99, -98, 98, -97, 97, -96, 96, },
{ -95, 95, -94, 94, -93, 93, -92, 92,
-91, 91, -90, 90, -89, 89, -88, 88,
-87, 87, -86, 86, -85, 85, -84, 84,
-83, 83, -82, 82, -81, 81, -80, 80,
-79, 79, -78, 78, -77, 77, -76, 76,
-75, 75, -74, 74, -73, 73, -72, 72,
-71, 71, -70, 70, -69, 69, -68, 68,
-67, 67, -66, 66, -65, 65, -64, 64, },
};
static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
{
DCTELEM *block = ctx->dct_block;
unsigned int pos;
ctx->dsp.clear_block(block);
block[0] = get_bits(&ctx->gb, 8) << 3;
for(pos = 1; pos < num_coeffs; pos++) {
uint32_t vlc, num_bits;
int value;
int coeff;
vlc = get_vlc2(&ctx->gb, ctx->vlc.table, ctx->vlc.bits, 3);
if(!vlc) /* end-of-block code */
return 1;
if(vlc == -1)
return 0;
/* pos_add and num_bits are coded in the vlc code */
pos += vlc&15; // pos_add
num_bits = vlc>>4; // num_bits
if(pos >= 64)
return 0;
value = get_bits(&ctx->gb, num_bits);
/* FFmpeg's IDCT behaves somewhat different from the original code, so
* a factor of 4 was added to the input */
coeff = vlcdec_lookup[num_bits][value];
if(pos<3)
coeff <<= 4;
else /* TODO Use >> 10 instead of / 1001 */
coeff = (coeff * qscale) / 1001;
block[ctx->scantable.permutated[pos]] = coeff;
}
return 1;
}
static int decode(MimicContext *ctx, int quality, int num_coeffs,
int is_iframe)
{
int y, x, plane;
for(plane = 0; plane < 3; plane++) {
const int is_chroma = !!plane;
const int qscale = av_clip(10000-quality,is_chroma?1000:2000,10000)<<2;
const int stride = ctx->flipped_ptrs[ctx->cur_index].linesize[plane];
const uint8_t *src = ctx->flipped_ptrs[ctx->prev_index].data[plane];
uint8_t *dst = ctx->flipped_ptrs[ctx->cur_index ].data[plane];
for(y = 0; y < ctx->num_vblocks[plane]; y++) {
for(x = 0; x < ctx->num_hblocks[plane]; x++) {
/* Check for a change condition in the current block.
* - iframes always change.
* - Luma plane changes on get_bits1 == 0
* - Chroma planes change on get_bits1 == 1 */
if(is_iframe || get_bits1(&ctx->gb) == is_chroma) {
/* Luma planes may use a backreference from the 15 last
* frames preceding the previous. (get_bits1 == 1)
* Chroma planes don't use backreferences. */
if(is_chroma || is_iframe || !get_bits1(&ctx->gb)) {
if(!vlc_decode_block(ctx, num_coeffs, qscale))
return 0;
ctx->dsp.idct_put(dst, stride, ctx->dct_block);
} else {
unsigned int backref = get_bits(&ctx->gb, 4);
int index = (ctx->cur_index+backref)&15;
uint8_t *p = ctx->flipped_ptrs[index].data[0];
if(p) {
p += src -
ctx->flipped_ptrs[ctx->prev_index].data[plane];
ctx->dsp.put_pixels_tab[1][0](dst, p, stride, 8);
} else {
av_log(ctx->avctx, AV_LOG_ERROR,
"No such backreference! Buggy sample.\n");
}
}
} else {
ctx->dsp.put_pixels_tab[1][0](dst, src, stride, 8);
}
src += 8;
dst += 8;
}
src += (stride - ctx->num_hblocks[plane])<<3;
dst += (stride - ctx->num_hblocks[plane])<<3;
}
}
return 1;
}
/**
* Flip the buffer upside-down and put it in the YVU order to match the
* way Mimic encodes frames.
*/
static void prepare_avpic(MimicContext *ctx, AVPicture *dst, AVPicture *src)
{
int i;
dst->data[0] = src->data[0]+( ctx->avctx->height -1)*src->linesize[0];
dst->data[1] = src->data[2]+((ctx->avctx->height>>1)-1)*src->linesize[2];
dst->data[2] = src->data[1]+((ctx->avctx->height>>1)-1)*src->linesize[1];
for(i = 0; i < 3; i++)
dst->linesize[i] = -src->linesize[i];
}
static int mimic_decode_frame(AVCodecContext *avctx, void *data,
int *data_size, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
MimicContext *ctx = avctx->priv_data;
int is_pframe;
int width, height;
int quality, num_coeffs;
int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
if(buf_size < MIMIC_HEADER_SIZE) {
av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
return -1;
}
buf += 2; /* some constant (always 256) */
quality = bytestream_get_le16(&buf);
width = bytestream_get_le16(&buf);
height = bytestream_get_le16(&buf);
buf += 4; /* some constant */
is_pframe = bytestream_get_le32(&buf);
num_coeffs = bytestream_get_byte(&buf);
buf += 3; /* some constant */
if(!ctx->avctx) {
int i;
if(!(width == 160 && height == 120) &&
!(width == 320 && height == 240)) {
av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
return -1;
}
ctx->avctx = avctx;
avctx->width = width;
avctx->height = height;
avctx->pix_fmt = PIX_FMT_YUV420P;
for(i = 0; i < 3; i++) {
ctx->num_vblocks[i] = -((-height) >> (3 + !!i));
ctx->num_hblocks[i] = width >> (3 + !!i) ;
}
} else if(width != ctx->avctx->width || height != ctx->avctx->height) {
av_log(avctx, AV_LOG_ERROR, "resolution changing is not supported\n");
return -1;
}
if(is_pframe && !ctx->buf_ptrs[ctx->prev_index].data[0]) {
av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
return -1;
}
ctx->buf_ptrs[ctx->cur_index].reference = 1;
if(avctx->get_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index])) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return -1;
}
prepare_avpic(ctx, &ctx->flipped_ptrs[ctx->cur_index],
(AVPicture*) &ctx->buf_ptrs[ctx->cur_index]);
av_fast_malloc(&ctx->swap_buf, &ctx->swap_buf_size,
swap_buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
if(!ctx->swap_buf)
return AVERROR(ENOMEM);
ctx->dsp.bswap_buf(ctx->swap_buf,
(const uint32_t*) buf,
swap_buf_size>>2);
init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);
if(!decode(ctx, quality, num_coeffs, !is_pframe)) {
avctx->release_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index]);
return -1;
}
ctx->buf_ptrs[ctx->cur_index].pict_type = is_pframe ? FF_P_TYPE:FF_I_TYPE;
*(AVFrame*)data = ctx->buf_ptrs[ctx->cur_index];
*data_size = sizeof(AVFrame);
ctx->prev_index = ctx->cur_index;
ctx->cur_index--;
ctx->cur_index &= 15;
/* Only release frames that aren't used for backreferences anymore */
if(ctx->buf_ptrs[ctx->cur_index].data[0])
avctx->release_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index]);
return buf_size;
}
static av_cold int mimic_decode_end(AVCodecContext *avctx)
{
MimicContext *ctx = avctx->priv_data;
int i;
av_free(ctx->swap_buf);
for(i = 0; i < 16; i++)
if(ctx->buf_ptrs[i].data[0])
avctx->release_buffer(avctx, &ctx->buf_ptrs[i]);
free_vlc(&ctx->vlc);
return 0;
}
AVCodec mimic_decoder = {
"mimic",
AVMEDIA_TYPE_VIDEO,
CODEC_ID_MIMIC,
sizeof(MimicContext),
mimic_decode_init,
NULL,
mimic_decode_end,
mimic_decode_frame,
CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Mimic"),
};