292 lines
9.0 KiB
C
292 lines
9.0 KiB
C
|
/*
|
||
|
* Flash Screen Video encoder
|
||
|
* Copyright (C) 2004 Alex Beregszaszi
|
||
|
* Copyright (C) 2006 Benjamin Larsson
|
||
|
*
|
||
|
* 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
|
||
|
*/
|
||
|
|
||
|
/* Encoding development sponsored by http://fh-campuswien.ac.at */
|
||
|
|
||
|
/**
|
||
|
* @file
|
||
|
* Flash Screen Video encoder
|
||
|
* @author Alex Beregszaszi
|
||
|
* @author Benjamin Larsson
|
||
|
*
|
||
|
* A description of the bitstream format for Flash Screen Video version 1/2
|
||
|
* is part of the SWF File Format Specification (version 10), which can be
|
||
|
* downloaded from http://www.adobe.com/devnet/swf.html.
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
* Encoding ideas: A basic encoder would just use a fixed block size.
|
||
|
* Block sizes can be multiples of 16, from 16 to 256. The blocks don't
|
||
|
* have to be quadratic. A brute force search with a set of different
|
||
|
* block sizes should give a better result than to just use a fixed size.
|
||
|
*
|
||
|
* TODO:
|
||
|
* Don't reencode the frame in brute force mode if the frame is a dupe.
|
||
|
* Speed up. Make the difference check faster.
|
||
|
*/
|
||
|
|
||
|
#include <stdio.h>
|
||
|
#include <stdlib.h>
|
||
|
#include <zlib.h>
|
||
|
|
||
|
#include "avcodec.h"
|
||
|
#include "internal.h"
|
||
|
#include "put_bits.h"
|
||
|
#include "bytestream.h"
|
||
|
|
||
|
|
||
|
typedef struct FlashSVContext {
|
||
|
AVCodecContext *avctx;
|
||
|
uint8_t *previous_frame;
|
||
|
int image_width, image_height;
|
||
|
int block_width, block_height;
|
||
|
uint8_t *tmpblock;
|
||
|
uint8_t *encbuffer;
|
||
|
int block_size;
|
||
|
z_stream zstream;
|
||
|
int last_key_frame;
|
||
|
} FlashSVContext;
|
||
|
|
||
|
static int copy_region_enc(uint8_t *sptr, uint8_t *dptr, int dx, int dy,
|
||
|
int h, int w, int stride, uint8_t *pfptr)
|
||
|
{
|
||
|
int i, j;
|
||
|
uint8_t *nsptr;
|
||
|
uint8_t *npfptr;
|
||
|
int diff = 0;
|
||
|
|
||
|
for (i = dx + h; i > dx; i--) {
|
||
|
nsptr = sptr + i * stride + dy * 3;
|
||
|
npfptr = pfptr + i * stride + dy * 3;
|
||
|
for (j = 0; j < w * 3; j++) {
|
||
|
diff |= npfptr[j] ^ nsptr[j];
|
||
|
dptr[j] = nsptr[j];
|
||
|
}
|
||
|
dptr += w * 3;
|
||
|
}
|
||
|
if (diff)
|
||
|
return 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static av_cold int flashsv_encode_end(AVCodecContext *avctx)
|
||
|
{
|
||
|
FlashSVContext *s = avctx->priv_data;
|
||
|
|
||
|
deflateEnd(&s->zstream);
|
||
|
|
||
|
av_freep(&s->encbuffer);
|
||
|
av_freep(&s->previous_frame);
|
||
|
av_freep(&s->tmpblock);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static av_cold int flashsv_encode_init(AVCodecContext *avctx)
|
||
|
{
|
||
|
FlashSVContext *s = avctx->priv_data;
|
||
|
|
||
|
s->avctx = avctx;
|
||
|
|
||
|
if (avctx->width > 4095 || avctx->height > 4095) {
|
||
|
av_log(avctx, AV_LOG_ERROR,
|
||
|
"Input dimensions too large, input must be max 4095x4095 !\n");
|
||
|
return AVERROR_INVALIDDATA;
|
||
|
}
|
||
|
|
||
|
// Needed if zlib unused or init aborted before deflateInit
|
||
|
memset(&s->zstream, 0, sizeof(z_stream));
|
||
|
|
||
|
s->last_key_frame = 0;
|
||
|
|
||
|
s->image_width = avctx->width;
|
||
|
s->image_height = avctx->height;
|
||
|
|
||
|
s->tmpblock = av_mallocz(3 * 256 * 256);
|
||
|
s->encbuffer = av_mallocz(s->image_width * s->image_height * 3);
|
||
|
|
||
|
if (!s->tmpblock || !s->encbuffer) {
|
||
|
av_log(avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
|
||
|
return AVERROR(ENOMEM);
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
|
||
|
static int encode_bitstream(FlashSVContext *s, const AVFrame *p, uint8_t *buf,
|
||
|
int buf_size, int block_width, int block_height,
|
||
|
uint8_t *previous_frame, int *I_frame)
|
||
|
{
|
||
|
|
||
|
PutBitContext pb;
|
||
|
int h_blocks, v_blocks, h_part, v_part, i, j;
|
||
|
int buf_pos, res;
|
||
|
int pred_blocks = 0;
|
||
|
|
||
|
init_put_bits(&pb, buf, buf_size);
|
||
|
|
||
|
put_bits(&pb, 4, block_width / 16 - 1);
|
||
|
put_bits(&pb, 12, s->image_width);
|
||
|
put_bits(&pb, 4, block_height / 16 - 1);
|
||
|
put_bits(&pb, 12, s->image_height);
|
||
|
flush_put_bits(&pb);
|
||
|
buf_pos = 4;
|
||
|
|
||
|
h_blocks = s->image_width / block_width;
|
||
|
h_part = s->image_width % block_width;
|
||
|
v_blocks = s->image_height / block_height;
|
||
|
v_part = s->image_height % block_height;
|
||
|
|
||
|
/* loop over all block columns */
|
||
|
for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
|
||
|
|
||
|
int y_pos = j * block_height; // vertical position in frame
|
||
|
int cur_blk_height = (j < v_blocks) ? block_height : v_part;
|
||
|
|
||
|
/* loop over all block rows */
|
||
|
for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
|
||
|
int x_pos = i * block_width; // horizontal position in frame
|
||
|
int cur_blk_width = (i < h_blocks) ? block_width : h_part;
|
||
|
int ret = Z_OK;
|
||
|
uint8_t *ptr = buf + buf_pos;
|
||
|
|
||
|
/* copy the block to the temp buffer before compression
|
||
|
* (if it differs from the previous frame's block) */
|
||
|
res = copy_region_enc(p->data[0], s->tmpblock,
|
||
|
s->image_height - (y_pos + cur_blk_height + 1),
|
||
|
x_pos, cur_blk_height, cur_blk_width,
|
||
|
p->linesize[0], previous_frame);
|
||
|
|
||
|
if (res || *I_frame) {
|
||
|
unsigned long zsize = 3 * block_width * block_height;
|
||
|
ret = compress2(ptr + 2, &zsize, s->tmpblock,
|
||
|
3 * cur_blk_width * cur_blk_height, 9);
|
||
|
|
||
|
//ret = deflateReset(&s->zstream);
|
||
|
if (ret != Z_OK)
|
||
|
av_log(s->avctx, AV_LOG_ERROR,
|
||
|
"error while compressing block %dx%d\n", i, j);
|
||
|
|
||
|
bytestream_put_be16(&ptr, zsize);
|
||
|
buf_pos += zsize + 2;
|
||
|
ff_dlog(s->avctx, "buf_pos = %d\n", buf_pos);
|
||
|
} else {
|
||
|
pred_blocks++;
|
||
|
bytestream_put_be16(&ptr, 0);
|
||
|
buf_pos += 2;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (pred_blocks)
|
||
|
*I_frame = 0;
|
||
|
else
|
||
|
*I_frame = 1;
|
||
|
|
||
|
return buf_pos;
|
||
|
}
|
||
|
|
||
|
|
||
|
static int flashsv_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
|
||
|
const AVFrame *pict, int *got_packet)
|
||
|
{
|
||
|
FlashSVContext * const s = avctx->priv_data;
|
||
|
const AVFrame * const p = pict;
|
||
|
uint8_t *pfptr;
|
||
|
int res;
|
||
|
int I_frame = 0;
|
||
|
int opt_w = 4, opt_h = 4;
|
||
|
|
||
|
/* First frame needs to be a keyframe */
|
||
|
if (avctx->frame_number == 0) {
|
||
|
s->previous_frame = av_mallocz(FFABS(p->linesize[0]) * s->image_height);
|
||
|
if (!s->previous_frame) {
|
||
|
av_log(avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
|
||
|
return AVERROR(ENOMEM);
|
||
|
}
|
||
|
I_frame = 1;
|
||
|
}
|
||
|
|
||
|
if (p->linesize[0] < 0)
|
||
|
pfptr = s->previous_frame - (s->image_height - 1) * p->linesize[0];
|
||
|
else
|
||
|
pfptr = s->previous_frame;
|
||
|
|
||
|
/* Check the placement of keyframes */
|
||
|
if (avctx->gop_size > 0 &&
|
||
|
avctx->frame_number >= s->last_key_frame + avctx->gop_size) {
|
||
|
I_frame = 1;
|
||
|
}
|
||
|
|
||
|
if ((res = ff_alloc_packet2(avctx, pkt, s->image_width * s->image_height * 3, 0)) < 0)
|
||
|
return res;
|
||
|
|
||
|
pkt->size = encode_bitstream(s, p, pkt->data, pkt->size, opt_w * 16, opt_h * 16,
|
||
|
pfptr, &I_frame);
|
||
|
|
||
|
//save the current frame
|
||
|
if (p->linesize[0] > 0)
|
||
|
memcpy(s->previous_frame, p->data[0], s->image_height * p->linesize[0]);
|
||
|
else
|
||
|
memcpy(s->previous_frame,
|
||
|
p->data[0] + p->linesize[0] * (s->image_height - 1),
|
||
|
s->image_height * FFABS(p->linesize[0]));
|
||
|
|
||
|
//mark the frame type so the muxer can mux it correctly
|
||
|
if (I_frame) {
|
||
|
#if FF_API_CODED_FRAME
|
||
|
FF_DISABLE_DEPRECATION_WARNINGS
|
||
|
avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
|
||
|
avctx->coded_frame->key_frame = 1;
|
||
|
FF_ENABLE_DEPRECATION_WARNINGS
|
||
|
#endif
|
||
|
s->last_key_frame = avctx->frame_number;
|
||
|
ff_dlog(avctx, "Inserting keyframe at frame %d\n", avctx->frame_number);
|
||
|
} else {
|
||
|
#if FF_API_CODED_FRAME
|
||
|
FF_DISABLE_DEPRECATION_WARNINGS
|
||
|
avctx->coded_frame->pict_type = AV_PICTURE_TYPE_P;
|
||
|
avctx->coded_frame->key_frame = 0;
|
||
|
FF_ENABLE_DEPRECATION_WARNINGS
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
if (I_frame)
|
||
|
pkt->flags |= AV_PKT_FLAG_KEY;
|
||
|
*got_packet = 1;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
AVCodec ff_flashsv_encoder = {
|
||
|
.name = "flashsv",
|
||
|
.long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video"),
|
||
|
.type = AVMEDIA_TYPE_VIDEO,
|
||
|
.id = AV_CODEC_ID_FLASHSV,
|
||
|
.priv_data_size = sizeof(FlashSVContext),
|
||
|
.init = flashsv_encode_init,
|
||
|
.encode2 = flashsv_encode_frame,
|
||
|
.close = flashsv_encode_end,
|
||
|
.pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
|
||
|
};
|