ffmpeg/libavcodec/bitpacked.c

150 lines
4.3 KiB
C

/*
* Unpack bit-packed streams to formats supported by FFmpeg
* Copyright (c) 2017 Savoir-faire Linux, Inc
*
* 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
*/
/* Development sponsored by CBC/Radio-Canada */
/**
* @file
* Bitpacked
*/
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
#include "libavutil/imgutils.h"
struct BitpackedContext {
int (*decode)(AVCodecContext *avctx, AVFrame *frame,
AVPacket *pkt);
};
/* For this format, it's a simple passthrough */
static int bitpacked_decode_uyvy422(AVCodecContext *avctx, AVFrame *frame,
AVPacket *avpkt)
{
int ret;
/* there is no need to copy as the data already match
* a known pixel format */
frame->buf[0] = av_buffer_ref(avpkt->buf);
ret = av_image_fill_arrays(frame->data, frame->linesize, avpkt->data,
avctx->pix_fmt, avctx->width, avctx->height, 1);
if (ret < 0) {
av_buffer_unref(&frame->buf[0]);
return ret;
}
return 0;
}
static int bitpacked_decode_yuv422p10(AVCodecContext *avctx, AVFrame *frame,
AVPacket *avpkt)
{
uint64_t frame_size = (uint64_t)avctx->width * (uint64_t)avctx->height * 20;
uint64_t packet_size = (uint64_t)avpkt->size * 8;
GetBitContext bc;
uint16_t *y, *u, *v;
int ret, i, j;
ret = ff_get_buffer(avctx, frame, 0);
if (ret < 0)
return ret;
if (frame_size > packet_size)
return AVERROR_INVALIDDATA;
if (avctx->width % 2)
return AVERROR_PATCHWELCOME;
ret = init_get_bits(&bc, avpkt->data, avctx->width * avctx->height * 20);
if (ret)
return ret;
for (i = 0; i < avctx->height; i++) {
y = (uint16_t*)(frame->data[0] + i * frame->linesize[0]);
u = (uint16_t*)(frame->data[1] + i * frame->linesize[1]);
v = (uint16_t*)(frame->data[2] + i * frame->linesize[2]);
for (j = 0; j < avctx->width; j += 2) {
*u++ = get_bits(&bc, 10);
*y++ = get_bits(&bc, 10);
*v++ = get_bits(&bc, 10);
*y++ = get_bits(&bc, 10);
}
}
return 0;
}
static av_cold int bitpacked_init_decoder(AVCodecContext *avctx)
{
struct BitpackedContext *bc = avctx->priv_data;
if (!avctx->codec_tag || !avctx->width || !avctx->height)
return AVERROR_INVALIDDATA;
if (avctx->codec_tag == MKTAG('U', 'Y', 'V', 'Y')) {
if (avctx->bits_per_coded_sample == 16 &&
avctx->pix_fmt == AV_PIX_FMT_UYVY422)
bc->decode = bitpacked_decode_uyvy422;
else if (avctx->bits_per_coded_sample == 20 &&
avctx->pix_fmt == AV_PIX_FMT_YUV422P10)
bc->decode = bitpacked_decode_yuv422p10;
else
return AVERROR_INVALIDDATA;
} else {
return AVERROR_INVALIDDATA;
}
return 0;
}
static int bitpacked_decode(AVCodecContext *avctx, void *data, int *got_frame,
AVPacket *avpkt)
{
struct BitpackedContext *bc = avctx->priv_data;
int buf_size = avpkt->size;
AVFrame *frame = data;
int res;
frame->pict_type = AV_PICTURE_TYPE_I;
frame->key_frame = 1;
res = bc->decode(avctx, frame, avpkt);
if (res)
return res;
*got_frame = 1;
return buf_size;
}
AVCodec ff_bitpacked_decoder = {
.name = "bitpacked",
.long_name = NULL_IF_CONFIG_SMALL("Bitpacked"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_BITPACKED,
.priv_data_size = sizeof(struct BitpackedContext),
.init = bitpacked_init_decoder,
.decode = bitpacked_decode,
.capabilities = AV_CODEC_CAP_EXPERIMENTAL,
};