mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-23 12:43:46 +02:00
328 lines
10 KiB
C
328 lines
10 KiB
C
/*
|
|
* QPEG codec
|
|
* Copyright (c) 2004 Konstantin Shishkov
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav 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.
|
|
*
|
|
* Libav 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 Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* QPEG codec.
|
|
*/
|
|
|
|
#include "avcodec.h"
|
|
#include "bytestream.h"
|
|
#include "internal.h"
|
|
|
|
typedef struct QpegContext{
|
|
AVCodecContext *avctx;
|
|
AVFrame pic;
|
|
uint8_t *refdata;
|
|
uint32_t pal[256];
|
|
GetByteContext buffer;
|
|
} QpegContext;
|
|
|
|
static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst,
|
|
int stride, int width, int height)
|
|
{
|
|
int i;
|
|
int code;
|
|
int c0, c1;
|
|
int run, copy;
|
|
int filled = 0;
|
|
int rows_to_go;
|
|
|
|
rows_to_go = height;
|
|
height--;
|
|
dst = dst + height * stride;
|
|
|
|
while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (rows_to_go > 0)) {
|
|
code = bytestream2_get_byte(&qctx->buffer);
|
|
run = copy = 0;
|
|
if(code == 0xFC) /* end-of-picture code */
|
|
break;
|
|
if(code >= 0xF8) { /* very long run */
|
|
c0 = bytestream2_get_byte(&qctx->buffer);
|
|
c1 = bytestream2_get_byte(&qctx->buffer);
|
|
run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2;
|
|
} else if (code >= 0xF0) { /* long run */
|
|
c0 = bytestream2_get_byte(&qctx->buffer);
|
|
run = ((code & 0xF) << 8) + c0 + 2;
|
|
} else if (code >= 0xE0) { /* short run */
|
|
run = (code & 0x1F) + 2;
|
|
} else if (code >= 0xC0) { /* very long copy */
|
|
c0 = bytestream2_get_byte(&qctx->buffer);
|
|
c1 = bytestream2_get_byte(&qctx->buffer);
|
|
copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1;
|
|
} else if (code >= 0x80) { /* long copy */
|
|
c0 = bytestream2_get_byte(&qctx->buffer);
|
|
copy = ((code & 0x7F) << 8) + c0 + 1;
|
|
} else { /* short copy */
|
|
copy = code + 1;
|
|
}
|
|
|
|
/* perform actual run or copy */
|
|
if(run) {
|
|
int p;
|
|
|
|
p = bytestream2_get_byte(&qctx->buffer);
|
|
for(i = 0; i < run; i++) {
|
|
dst[filled++] = p;
|
|
if (filled >= width) {
|
|
filled = 0;
|
|
dst -= stride;
|
|
rows_to_go--;
|
|
if(rows_to_go <= 0)
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
for(i = 0; i < copy; i++) {
|
|
dst[filled++] = bytestream2_get_byte(&qctx->buffer);
|
|
if (filled >= width) {
|
|
filled = 0;
|
|
dst -= stride;
|
|
rows_to_go--;
|
|
if(rows_to_go <= 0)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static const int qpeg_table_h[16] =
|
|
{ 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04};
|
|
static const int qpeg_table_w[16] =
|
|
{ 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04};
|
|
|
|
/* Decodes delta frames */
|
|
static void qpeg_decode_inter(QpegContext *qctx, uint8_t *dst,
|
|
int stride, int width, int height,
|
|
int delta, const uint8_t *ctable,
|
|
uint8_t *refdata)
|
|
{
|
|
int i, j;
|
|
int code;
|
|
int filled = 0;
|
|
int orig_height;
|
|
|
|
/* copy prev frame */
|
|
for(i = 0; i < height; i++)
|
|
memcpy(refdata + (i * width), dst + (i * stride), width);
|
|
|
|
orig_height = height;
|
|
height--;
|
|
dst = dst + height * stride;
|
|
|
|
while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (height >= 0)) {
|
|
code = bytestream2_get_byte(&qctx->buffer);
|
|
|
|
if(delta) {
|
|
/* motion compensation */
|
|
while((code & 0xF0) == 0xF0) {
|
|
if(delta == 1) {
|
|
int me_idx;
|
|
int me_w, me_h, me_x, me_y;
|
|
uint8_t *me_plane;
|
|
int corr, val;
|
|
|
|
/* get block size by index */
|
|
me_idx = code & 0xF;
|
|
me_w = qpeg_table_w[me_idx];
|
|
me_h = qpeg_table_h[me_idx];
|
|
|
|
/* extract motion vector */
|
|
corr = bytestream2_get_byte(&qctx->buffer);
|
|
|
|
val = corr >> 4;
|
|
if(val > 7)
|
|
val -= 16;
|
|
me_x = val;
|
|
|
|
val = corr & 0xF;
|
|
if(val > 7)
|
|
val -= 16;
|
|
me_y = val;
|
|
|
|
/* check motion vector */
|
|
if ((me_x + filled < 0) || (me_x + me_w + filled > width) ||
|
|
(height - me_y - me_h < 0) || (height - me_y > orig_height) ||
|
|
(filled + me_w > width) || (height - me_h < 0))
|
|
av_log(NULL, AV_LOG_ERROR, "Bogus motion vector (%i,%i), block size %ix%i at %i,%i\n",
|
|
me_x, me_y, me_w, me_h, filled, height);
|
|
else {
|
|
/* do motion compensation */
|
|
me_plane = refdata + (filled + me_x) + (height - me_y) * width;
|
|
for(j = 0; j < me_h; j++) {
|
|
for(i = 0; i < me_w; i++)
|
|
dst[filled + i - (j * stride)] = me_plane[i - (j * width)];
|
|
}
|
|
}
|
|
}
|
|
code = bytestream2_get_byte(&qctx->buffer);
|
|
}
|
|
}
|
|
|
|
if(code == 0xE0) /* end-of-picture code */
|
|
break;
|
|
if(code > 0xE0) { /* run code: 0xE1..0xFF */
|
|
int p;
|
|
|
|
code &= 0x1F;
|
|
p = bytestream2_get_byte(&qctx->buffer);
|
|
for(i = 0; i <= code; i++) {
|
|
dst[filled++] = p;
|
|
if(filled >= width) {
|
|
filled = 0;
|
|
dst -= stride;
|
|
height--;
|
|
if (height < 0)
|
|
break;
|
|
}
|
|
}
|
|
} else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */
|
|
code &= 0x1F;
|
|
|
|
for(i = 0; i <= code; i++) {
|
|
dst[filled++] = bytestream2_get_byte(&qctx->buffer);
|
|
if(filled >= width) {
|
|
filled = 0;
|
|
dst -= stride;
|
|
height--;
|
|
if (height < 0)
|
|
break;
|
|
}
|
|
}
|
|
} else if(code >= 0x80) { /* skip code: 0x80..0xBF */
|
|
int skip;
|
|
|
|
code &= 0x3F;
|
|
/* codes 0x80 and 0x81 are actually escape codes,
|
|
skip value minus constant is in the next byte */
|
|
if(!code)
|
|
skip = bytestream2_get_byte(&qctx->buffer) + 64;
|
|
else if(code == 1)
|
|
skip = bytestream2_get_byte(&qctx->buffer) + 320;
|
|
else
|
|
skip = code;
|
|
filled += skip;
|
|
while( filled >= width) {
|
|
filled -= width;
|
|
dst -= stride;
|
|
height--;
|
|
if(height < 0)
|
|
break;
|
|
}
|
|
} else {
|
|
/* zero code treated as one-pixel skip */
|
|
if(code) {
|
|
dst[filled++] = ctable[code & 0x7F];
|
|
}
|
|
else
|
|
filled++;
|
|
if(filled >= width) {
|
|
filled = 0;
|
|
dst -= stride;
|
|
height--;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int decode_frame(AVCodecContext *avctx,
|
|
void *data, int *got_frame,
|
|
AVPacket *avpkt)
|
|
{
|
|
uint8_t ctable[128];
|
|
QpegContext * const a = avctx->priv_data;
|
|
AVFrame * const p = &a->pic;
|
|
uint8_t* outdata;
|
|
int delta, ret;
|
|
const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
|
|
|
|
if (avpkt->size < 0x86) {
|
|
av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
bytestream2_init(&a->buffer, avpkt->data, avpkt->size);
|
|
if ((ret = ff_reget_buffer(avctx, p)) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
|
|
return ret;
|
|
}
|
|
outdata = a->pic.data[0];
|
|
bytestream2_skip(&a->buffer, 4);
|
|
bytestream2_get_buffer(&a->buffer, ctable, 128);
|
|
bytestream2_skip(&a->buffer, 1);
|
|
|
|
delta = bytestream2_get_byte(&a->buffer);
|
|
if(delta == 0x10) {
|
|
qpeg_decode_intra(a, outdata, a->pic.linesize[0], avctx->width, avctx->height);
|
|
} else {
|
|
qpeg_decode_inter(a, outdata, a->pic.linesize[0], avctx->width, avctx->height, delta, ctable, a->refdata);
|
|
}
|
|
|
|
/* make the palette available on the way out */
|
|
if (pal) {
|
|
a->pic.palette_has_changed = 1;
|
|
memcpy(a->pal, pal, AVPALETTE_SIZE);
|
|
}
|
|
memcpy(a->pic.data[1], a->pal, AVPALETTE_SIZE);
|
|
|
|
if ((ret = av_frame_ref(data, &a->pic)) < 0)
|
|
return ret;
|
|
|
|
*got_frame = 1;
|
|
|
|
return avpkt->size;
|
|
}
|
|
|
|
static av_cold int decode_init(AVCodecContext *avctx){
|
|
QpegContext * const a = avctx->priv_data;
|
|
|
|
a->avctx = avctx;
|
|
avctx->pix_fmt= AV_PIX_FMT_PAL8;
|
|
a->refdata = av_malloc(avctx->width * avctx->height);
|
|
|
|
avcodec_get_frame_defaults(&a->pic);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int decode_end(AVCodecContext *avctx){
|
|
QpegContext * const a = avctx->priv_data;
|
|
AVFrame * const p = &a->pic;
|
|
|
|
av_frame_unref(p);
|
|
|
|
av_free(a->refdata);
|
|
return 0;
|
|
}
|
|
|
|
AVCodec ff_qpeg_decoder = {
|
|
.name = "qpeg",
|
|
.long_name = NULL_IF_CONFIG_SMALL("Q-team QPEG"),
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.id = AV_CODEC_ID_QPEG,
|
|
.priv_data_size = sizeof(QpegContext),
|
|
.init = decode_init,
|
|
.close = decode_end,
|
|
.decode = decode_frame,
|
|
.capabilities = CODEC_CAP_DR1,
|
|
};
|