FFmpeg/libavcodec/cllc.c
Reimar Döffinger 998f92d680 cllc: simplify/fix swapped data buffer allocation.
Using the malloc variant avoids pointless memcpy on size
increase and simplifies handling allocation failure.
Also change code to ensure that allocation, bswap and bitstream
reader all use the same size, even when the packet size is odd
for example.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
2012-08-28 11:37:53 -04:00

420 lines
10 KiB
C

/*
* Canopus Lossless Codec decoder
*
* Copyright (c) 2012 Derek Buitenhuis
*
* 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 "libavutil/intreadwrite.h"
#include "dsputil.h"
#include "get_bits.h"
#include "avcodec.h"
typedef struct CLLCContext {
DSPContext dsp;
AVCodecContext *avctx;
uint8_t *swapped_buf;
int swapped_buf_size;
} CLLCContext;
static int read_code_table(CLLCContext *ctx, GetBitContext *gb, VLC *vlc)
{
uint8_t symbols[256];
uint8_t bits[256];
uint16_t codes[256];
int num_lens, num_codes, num_codes_sum, prefix;
int i, j, count;
prefix = 0;
count = 0;
num_codes_sum = 0;
num_lens = get_bits(gb, 5);
for (i = 0; i < num_lens; i++) {
num_codes = get_bits(gb, 9);
num_codes_sum += num_codes;
if (num_codes_sum > 256) {
vlc->table = NULL;
av_log(ctx->avctx, AV_LOG_ERROR,
"Too many VLCs (%d) to be read.\n", num_codes_sum);
return AVERROR_INVALIDDATA;
}
for (j = 0; j < num_codes; j++) {
symbols[count] = get_bits(gb, 8);
bits[count] = i + 1;
codes[count] = prefix++;
count++;
}
prefix <<= 1;
}
return ff_init_vlc_sparse(vlc, 7, count, bits, 1, 1,
codes, 2, 2, symbols, 1, 1, 0);
}
/*
* Unlike the RGB24 read/restore, which reads in a component at a time,
* ARGB read/restore reads in ARGB quads.
*/
static int read_argb_line(CLLCContext *ctx, GetBitContext *gb, int *top_left,
VLC *vlc, uint8_t *outbuf)
{
uint8_t *dst;
int pred[4];
int code;
int i;
OPEN_READER(bits, gb);
dst = outbuf;
pred[0] = top_left[0];
pred[1] = top_left[1];
pred[2] = top_left[2];
pred[3] = top_left[3];
for (i = 0; i < ctx->avctx->width; i++) {
/* Always get the alpha component */
UPDATE_CACHE(bits, gb);
GET_VLC(code, bits, gb, vlc[0].table, 7, 2);
pred[0] += code;
dst[0] = pred[0];
/* Skip the components if they are entirely transparent */
if (dst[0]) {
/* Red */
UPDATE_CACHE(bits, gb);
GET_VLC(code, bits, gb, vlc[1].table, 7, 2);
pred[1] += code;
dst[1] = pred[1];
/* Green */
UPDATE_CACHE(bits, gb);
GET_VLC(code, bits, gb, vlc[2].table, 7, 2);
pred[2] += code;
dst[2] = pred[2];
/* Blue */
UPDATE_CACHE(bits, gb);
GET_VLC(code, bits, gb, vlc[3].table, 7, 2);
pred[3] += code;
dst[3] = pred[3];
} else {
dst[1] = 0;
dst[2] = 0;
dst[3] = 0;
}
dst += 4;
}
CLOSE_READER(bits, gb);
dst -= 4 * ctx->avctx->width;
top_left[0] = dst[0];
/* Only stash components if they are not transparent */
if (top_left[0]) {
top_left[1] = dst[1];
top_left[2] = dst[2];
top_left[3] = dst[3];
}
return 0;
}
static int read_rgb24_component_line(CLLCContext *ctx, GetBitContext *gb,
int *top_left, VLC *vlc, uint8_t *outbuf)
{
uint8_t *dst;
int pred, code;
int i;
OPEN_READER(bits, gb);
dst = outbuf;
pred = *top_left;
/* Simultaneously read and restore the line */
for (i = 0; i < ctx->avctx->width; i++) {
UPDATE_CACHE(bits, gb);
GET_VLC(code, bits, gb, vlc->table, 7, 2);
pred += code;
dst[0] = pred;
dst += 3;
}
CLOSE_READER(bits, gb);
/* Stash the first pixel */
*top_left = dst[-3 * ctx->avctx->width];
return 0;
}
static int decode_argb_frame(CLLCContext *ctx, GetBitContext *gb, AVFrame *pic)
{
AVCodecContext *avctx = ctx->avctx;
uint8_t *dst;
int pred[4];
int ret;
int i, j;
VLC vlc[4];
pred[0] = 0;
pred[1] = 0x80;
pred[2] = 0x80;
pred[3] = 0x80;
dst = pic->data[0];
skip_bits(gb, 16);
/* Read in code table for each plane */
for (i = 0; i < 4; i++) {
ret = read_code_table(ctx, gb, &vlc[i]);
if (ret < 0) {
for (j = 0; j <= i; j++)
ff_free_vlc(&vlc[j]);
av_log(ctx->avctx, AV_LOG_ERROR,
"Could not read code table %d.\n", i);
return ret;
}
}
/* Read in and restore every line */
for (i = 0; i < avctx->height; i++) {
read_argb_line(ctx, gb, pred, vlc, dst);
dst += pic->linesize[0];
}
for (i = 0; i < 4; i++)
ff_free_vlc(&vlc[i]);
return 0;
}
static int decode_rgb24_frame(CLLCContext *ctx, GetBitContext *gb, AVFrame *pic)
{
AVCodecContext *avctx = ctx->avctx;
uint8_t *dst;
int pred[3];
int ret;
int i, j;
VLC vlc[3];
pred[0] = 0x80;
pred[1] = 0x80;
pred[2] = 0x80;
dst = pic->data[0];
skip_bits(gb, 16);
/* Read in code table for each plane */
for (i = 0; i < 3; i++) {
ret = read_code_table(ctx, gb, &vlc[i]);
if (ret < 0) {
for (j = 0; j <= i; j++)
ff_free_vlc(&vlc[j]);
av_log(ctx->avctx, AV_LOG_ERROR,
"Could not read code table %d.\n", i);
return ret;
}
}
/* Read in and restore every line */
for (i = 0; i < avctx->height; i++) {
for (j = 0; j < 3; j++)
read_rgb24_component_line(ctx, gb, &pred[j], &vlc[j], &dst[j]);
dst += pic->linesize[0];
}
for (i = 0; i < 3; i++)
ff_free_vlc(&vlc[i]);
return 0;
}
static int cllc_decode_frame(AVCodecContext *avctx, void *data,
int *got_picture_ptr, AVPacket *avpkt)
{
CLLCContext *ctx = avctx->priv_data;
AVFrame *pic = avctx->coded_frame;
uint8_t *src = avpkt->data;
uint32_t info_tag, info_offset;
int data_size;
GetBitContext gb;
int coding_type, ret;
if (pic->data[0])
avctx->release_buffer(avctx, pic);
pic->reference = 0;
/* Skip the INFO header if present */
info_offset = 0;
info_tag = AV_RL32(src);
if (info_tag == MKTAG('I', 'N', 'F', 'O')) {
info_offset = AV_RL32(src + 4);
if (info_offset > UINT32_MAX - 8 || info_offset + 8 > avpkt->size) {
av_log(avctx, AV_LOG_ERROR,
"Invalid INFO header offset: 0x%08X is too large.\n",
info_offset);
return AVERROR_INVALIDDATA;
}
info_offset += 8;
src += info_offset;
av_log(avctx, AV_LOG_DEBUG, "Skipping INFO chunk.\n");
}
data_size = (avpkt->size - info_offset) & ~1;
/* Make sure our bswap16'd buffer is big enough */
av_fast_padded_malloc(&ctx->swapped_buf,
&ctx->swapped_buf_size, data_size);
if (!ctx->swapped_buf) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate swapped buffer.\n");
return AVERROR(ENOMEM);
}
/* bswap16 the buffer since CLLC's bitreader works in 16-bit words */
ctx->dsp.bswap16_buf((uint16_t *) ctx->swapped_buf, (uint16_t *) src,
data_size / 2);
init_get_bits(&gb, ctx->swapped_buf, data_size * 8);
/*
* Read in coding type. The types are as follows:
*
* 0 - YUY2
* 1 - BGR24 (Triples)
* 2 - BGR24 (Quads)
* 3 - BGRA
*/
coding_type = (AV_RL32(src) >> 8) & 0xFF;
av_log(avctx, AV_LOG_DEBUG, "Frame coding type: %d\n", coding_type);
switch (coding_type) {
case 1:
case 2:
avctx->pix_fmt = PIX_FMT_RGB24;
avctx->bits_per_raw_sample = 8;
ret = avctx->get_buffer(avctx, pic);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
return ret;
}
ret = decode_rgb24_frame(ctx, &gb, pic);
if (ret < 0)
return ret;
break;
case 3:
avctx->pix_fmt = PIX_FMT_ARGB;
avctx->bits_per_raw_sample = 8;
ret = avctx->get_buffer(avctx, pic);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
return ret;
}
ret = decode_argb_frame(ctx, &gb, pic);
if (ret < 0)
return ret;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown coding type: %d.\n", coding_type);
return AVERROR_INVALIDDATA;
}
pic->key_frame = 1;
pic->pict_type = AV_PICTURE_TYPE_I;
*got_picture_ptr = 1;
*(AVFrame *)data = *pic;
return avpkt->size;
}
static av_cold int cllc_decode_close(AVCodecContext *avctx)
{
CLLCContext *ctx = avctx->priv_data;
if (avctx->coded_frame->data[0])
avctx->release_buffer(avctx, avctx->coded_frame);
av_freep(&avctx->coded_frame);
av_freep(&ctx->swapped_buf);
return 0;
}
static av_cold int cllc_decode_init(AVCodecContext *avctx)
{
CLLCContext *ctx = avctx->priv_data;
/* Initialize various context values */
ctx->avctx = avctx;
ctx->swapped_buf = NULL;
ctx->swapped_buf_size = 0;
ff_dsputil_init(&ctx->dsp, avctx);
avctx->coded_frame = avcodec_alloc_frame();
if (!avctx->coded_frame) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate frame.\n");
return AVERROR(ENOMEM);
}
return 0;
}
AVCodec ff_cllc_decoder = {
.name = "cllc",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_CLLC,
.priv_data_size = sizeof(CLLCContext),
.init = cllc_decode_init,
.decode = cllc_decode_frame,
.close = cllc_decode_close,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Canopus Lossless Codec"),
};