/*
* Ut Video encoder
* Copyright (c) 2012 Jan Ekström
*
* 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
*/
/**
* @file
* Ut Video encoder
*/
#include "libavutil/imgutils.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "internal.h"
#include "bytestream.h"
#include "put_bits.h"
#include "dsputil.h"
#include "mathops.h"
#include "utvideo.h"
#include "huffman.h"
/* Compare huffentry symbols */
static int huff_cmp_sym(const void *a, const void *b)
{
const HuffEntry *aa = a, *bb = b;
return aa->sym - bb->sym;
}
static av_cold int utvideo_encode_close(AVCodecContext *avctx)
{
UtvideoContext *c = avctx->priv_data;
int i;
av_freep(&avctx->coded_frame);
av_freep(&c->slice_bits);
for (i = 0; i < 4; i++)
av_freep(&c->slice_buffer[i]);
return 0;
}
static av_cold int utvideo_encode_init(AVCodecContext *avctx)
{
UtvideoContext *c = avctx->priv_data;
int i;
uint32_t original_format;
c->avctx = avctx;
c->frame_info_size = 4;
c->slice_stride = FFALIGN(avctx->width, 32);
switch (avctx->pix_fmt) {
case AV_PIX_FMT_RGB24:
c->planes = 3;
avctx->codec_tag = MKTAG('U', 'L', 'R', 'G');
original_format = UTVIDEO_RGB;
break;
case AV_PIX_FMT_RGBA:
c->planes = 4;
avctx->codec_tag = MKTAG('U', 'L', 'R', 'A');
original_format = UTVIDEO_RGBA;
break;
case AV_PIX_FMT_YUV420P:
if (avctx->width & 1 || avctx->height & 1) {
av_log(avctx, AV_LOG_ERROR,
"4:2:0 video requires even width and height.\n");
return AVERROR_INVALIDDATA;
}
c->planes = 3;
avctx->codec_tag = MKTAG('U', 'L', 'Y', '0');
original_format = UTVIDEO_420;
break;
case AV_PIX_FMT_YUV422P:
if (avctx->width & 1) {
av_log(avctx, AV_LOG_ERROR,
"4:2:2 video requires even width.\n");
return AVERROR_INVALIDDATA;
}
c->planes = 3;
avctx->codec_tag = MKTAG('U', 'L', 'Y', '2');
original_format = UTVIDEO_422;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown pixel format: %d\n",
avctx->pix_fmt);
return AVERROR_INVALIDDATA;
}
ff_dsputil_init(&c->dsp, avctx);
/* Check the prediction method, and error out if unsupported */
if (avctx->prediction_method < 0 || avctx->prediction_method > 4) {
av_log(avctx, AV_LOG_WARNING,
"Prediction method %d is not supported in Ut Video.\n",
avctx->prediction_method);
return AVERROR_OPTION_NOT_FOUND;
}
if (avctx->prediction_method == FF_PRED_PLANE) {
av_log(avctx, AV_LOG_ERROR,
"Plane prediction is not supported in Ut Video.\n");
return AVERROR_OPTION_NOT_FOUND;
}
/* Convert from libavcodec prediction type to Ut Video's */
c->frame_pred = ff_ut_pred_order[avctx->prediction_method];
if (c->frame_pred == PRED_GRADIENT) {
av_log(avctx, AV_LOG_ERROR, "Gradient prediction is not supported.\n");
return AVERROR_OPTION_NOT_FOUND;
}
avctx->coded_frame = avcodec_alloc_frame();
if (!avctx->coded_frame) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate frame.\n");
utvideo_encode_close(avctx);
return AVERROR(ENOMEM);
}
/* extradata size is 4 * 32bit */
avctx->extradata_size = 16;
avctx->extradata = av_mallocz(avctx->extradata_size +
FF_INPUT_BUFFER_PADDING_SIZE);
if (!avctx->extradata) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate extradata.\n");
utvideo_encode_close(avctx);
return AVERROR(ENOMEM);
}
for (i = 0; i < c->planes; i++) {
c->slice_buffer[i] = av_malloc(c->slice_stride * (avctx->height + 2) +
FF_INPUT_BUFFER_PADDING_SIZE);
if (!c->slice_buffer[i]) {
av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer 1.\n");
utvideo_encode_close(avctx);
return AVERROR(ENOMEM);
}
}
/*
* Set the version of the encoder.
* Last byte is "implementation ID", which is
* obtained from the creator of the format.
* Libavcodec has been assigned with the ID 0xF0.
*/
AV_WB32(avctx->extradata, MKTAG(1, 0, 0, 0xF0));
/*
* Set the "original format"
* Not used for anything during decoding.
*/
AV_WL32(avctx->extradata + 4, original_format);
/* Write 4 as the 'frame info size' */
AV_WL32(avctx->extradata + 8, c->frame_info_size);
/*
* Set how many slices are going to be used.
* Set one slice for now.
*/
c->slices = 1;
/* Set compression mode */
c->compression = COMP_HUFF;
/*
* Set the encoding flags:
* - Slice count minus 1
* - Interlaced encoding mode flag, set to zero for now.
* - Compression mode (none/huff)
* And write the flags.
*/
c->flags = (c->slices - 1) << 24;
c->flags |= 0 << 11; // bit field to signal interlaced encoding mode
c->flags |= c->compression;
AV_WL32(avctx->extradata + 12, c->flags);
return 0;
}
static void mangle_rgb_planes(uint8_t *dst[4], int dst_stride, uint8_t *src,
int step, int stride, int width, int height)
{
int i, j;
int k = 2 * dst_stride;
unsigned int g;
for (j = 0; j < height; j++) {
if (step == 3) {
for (i = 0; i < width * step; i += step) {
g = src[i + 1];
dst[0][k] = g;
g += 0x80;
dst[1][k] = src[i + 2] - g;
dst[2][k] = src[i + 0] - g;
k++;
}
} else {
for (i = 0; i < width * step; i += step) {
g = src[i + 1];
dst[0][k] = g;
g += 0x80;
dst[1][k] = src[i + 2] - g;
dst[2][k] = src[i + 0] - g;
dst[3][k] = src[i + 3];
k++;
}
}
k += dst_stride - width;
src += stride;
}
}
/* Write data to a plane with left prediction */
static void left_predict(uint8_t *src, uint8_t *dst, int stride,
int width, int height)
{
int i, j;
uint8_t prev;
prev = 0x80; /* Set the initial value */
for (j = 0; j < height; j++) {
for (i = 0; i < width; i++) {
*dst++ = src[i] - prev;
prev = src[i];
}
src += stride;
}
}
/* Write data to a plane with median prediction */
static void median_predict(UtvideoContext *c, uint8_t *src, uint8_t *dst, int stride,
int width, int height)
{
int i, j;
int A, B;
uint8_t prev;
/* First line uses left neighbour prediction */
prev = 0x80; /* Set the initial value */
for (i = 0; i < width; i++) {
*dst++ = src[i] - prev;
prev = src[i];
}
if (height == 1)
return;
src += stride;
/*
* Second line uses top prediction for the first sample,
* and median for the rest.
*/
A = B = 0;
/* Rest of the coded part uses median prediction */
for (j = 1; j < height; j++) {
c->dsp.sub_hfyu_median_prediction(dst, src - stride, src, width, &A, &B);
dst += width;
src += stride;
}
}
/* Count the usage of values in a plane */
static void count_usage(uint8_t *src, int width,
int height, uint64_t *counts)
{
int i, j;
for (j = 0; j < height; j++) {
for (i = 0; i < width; i++) {
counts[src[i]]++;
}
src += width;
}
}
/* Calculate the actual huffman codes from the code lengths */
static void calculate_codes(HuffEntry *he)
{
int last, i;
uint32_t code;
qsort(he
, 256, sizeof(*he
), ff_ut_huff_cmp_len
);
last = 255;
while (he[last].len == 255 && last)
last--;
code = 1;
for (i = last; i >= 0; i--) {
he[i].code = code >> (32 - he[i].len);
code += 0x80000000u >> (he[i].len - 1);
}
qsort(he
, 256, sizeof(*he
), huff_cmp_sym
); }
/* Write huffman bit codes to a memory block */
static int write_huff_codes(uint8_t *src, uint8_t *dst, int dst_size,
int width, int height, HuffEntry *he)
{
PutBitContext pb;
int i, j;
int count;
init_put_bits(&pb, dst, dst_size);
/* Write the codes */
for (j = 0; j < height; j++) {
for (i = 0; i < width; i++)
put_bits(&pb, he[src[i]].len, he[src[i]].code);
src += width;
}
/* Pad output to a 32bit boundary */
count = put_bits_count(&pb) & 0x1F;
if (count)
put_bits(&pb, 32 - count, 0);
/* Get the amount of bits written */
count = put_bits_count(&pb);
/* Flush the rest with zeroes */
flush_put_bits(&pb);
return count;
}
static int encode_plane(AVCodecContext *avctx, uint8_t *src,
uint8_t *dst, int stride,
int width, int height, PutByteContext *pb)
{
UtvideoContext *c = avctx->priv_data;
uint8_t lengths[256];
uint64_t counts[256] = { 0 };
HuffEntry he[256];
uint32_t offset = 0, slice_len = 0;
int i, sstart, send = 0;
int symbol;
/* Do prediction / make planes */
switch (c->frame_pred) {
case PRED_NONE:
for (i = 0; i < c->slices; i++) {
sstart = send;
send = height * (i + 1) / c->slices;
av_image_copy_plane(dst + sstart * width, width,
src + sstart * stride, stride,
width, send - sstart);
}
break;
case PRED_LEFT:
for (i = 0; i < c->slices; i++) {
sstart = send;
send = height * (i + 1) / c->slices;
left_predict(src + sstart * stride, dst + sstart * width,
stride, width, send - sstart);
}
break;
case PRED_MEDIAN:
for (i = 0; i < c->slices; i++) {
sstart = send;
send = height * (i + 1) / c->slices;
median_predict(c, src + sstart * stride, dst + sstart * width,
stride, width, send - sstart);
}
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown prediction mode: %d\n",
c->frame_pred);
return AVERROR_OPTION_NOT_FOUND;
}
/* Count the usage of values */
count_usage(dst, width, height, counts);
/* Check for a special case where only one symbol was used */
for (symbol = 0; symbol < 256; symbol++) {
/* If non-zero count is found, see if it matches width * height */
if (counts[symbol]) {
/* Special case if only one symbol was used */
if (counts[symbol] == width * (int64_t)height) {
/*
* Write a zero for the single symbol
* used in the plane, else 0xFF.
*/
for (i = 0; i < 256; i++) {
if (i == symbol)
bytestream2_put_byte(pb, 0);
else
bytestream2_put_byte(pb, 0xFF);
}
/* Write zeroes for lengths */
for (i = 0; i < c->slices; i++)
bytestream2_put_le32(pb, 0);
/* And that's all for that plane folks */
return 0;
}
break;
}
}
/* Calculate huffman lengths */
ff_huff_gen_len_table(lengths, counts);
/*
* Write the plane's header into the output packet:
* - huffman code lengths (256 bytes)
* - slice end offsets (gotten from the slice lengths)
*/
for (i = 0; i < 256; i++) {
bytestream2_put_byte(pb, lengths[i]);
he[i].len = lengths[i];
he[i].sym = i;
}
/* Calculate the huffman codes themselves */
calculate_codes(he);
send = 0;
for (i = 0; i < c->slices; i++) {
sstart = send;
send = height * (i + 1) / c->slices;
/*
* Write the huffman codes to a buffer,
* get the offset in bits and convert to bytes.
*/
offset += write_huff_codes(dst + sstart * width, c->slice_bits,
width * (send - sstart), width,
send - sstart, he) >> 3;
slice_len = offset - slice_len;
/* Byteswap the written huffman codes */
c->dsp.bswap_buf((uint32_t *) c->slice_bits,
(uint32_t *) c->slice_bits,
slice_len >> 2);
/* Write the offset to the stream */
bytestream2_put_le32(pb, offset);
/* Seek to the data part of the packet */
bytestream2_seek_p(pb, 4 * (c->slices - i - 1) +
offset - slice_len, SEEK_CUR);
/* Write the slices' data into the output packet */
bytestream2_put_buffer(pb, c->slice_bits, slice_len);
/* Seek back to the slice offsets */
bytestream2_seek_p(pb, -4 * (c->slices - i - 1) - offset,
SEEK_CUR);
slice_len = offset;
}
/* And at the end seek to the end of written slice(s) */
bytestream2_seek_p(pb, offset, SEEK_CUR);
return 0;
}
static int utvideo_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *pic, int *got_packet)
{
UtvideoContext *c = avctx->priv_data;
PutByteContext pb;
uint32_t frame_info;
uint8_t *dst;
int width = avctx->width, height = avctx->height;
int i, ret = 0;
/* Allocate a new packet if needed, and set it to the pointer dst */
ret = ff_alloc_packet2(avctx, pkt, (256 + 4 * c->slices + width * height) *
c->planes + 4);
if (ret < 0)
return ret;
dst = pkt->data;
bytestream2_init_writer(&pb, dst, pkt->size);
av_fast_malloc(&c->slice_bits, &c->slice_bits_size,
width * height + FF_INPUT_BUFFER_PADDING_SIZE);
if (!c->slice_bits) {
av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer 2.\n");
return AVERROR(ENOMEM);
}
/* In case of RGB, mangle the planes to Ut Video's format */
if (avctx->pix_fmt == AV_PIX_FMT_RGBA || avctx->pix_fmt == AV_PIX_FMT_RGB24)
mangle_rgb_planes(c->slice_buffer, c->slice_stride, pic->data[0],
c->planes, pic->linesize[0], width, height);
/* Deal with the planes */
switch (avctx->pix_fmt) {
case AV_PIX_FMT_RGB24:
case AV_PIX_FMT_RGBA:
for (i = 0; i < c->planes; i++) {
ret = encode_plane(avctx, c->slice_buffer[i] + 2 * c->slice_stride,
c->slice_buffer[i], c->slice_stride,
width, height, &pb);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "Error encoding plane %d.\n", i);
return ret;
}
}
break;
case AV_PIX_FMT_YUV422P:
for (i = 0; i < c->planes; i++) {
ret = encode_plane(avctx, pic->data[i], c->slice_buffer[0],
pic->linesize[i], width >> !!i, height, &pb);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "Error encoding plane %d.\n", i);
return ret;
}
}
break;
case AV_PIX_FMT_YUV420P:
for (i = 0; i < c->planes; i++) {
ret = encode_plane(avctx, pic->data[i], c->slice_buffer[0],
pic->linesize[i], width >> !!i, height >> !!i,
&pb);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "Error encoding plane %d.\n", i);
return ret;
}
}
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown pixel format: %d\n",
avctx->pix_fmt);
return AVERROR_INVALIDDATA;
}
/*
* Write frame information (LE 32bit unsigned)
* into the output packet.
* Contains the prediction method.
*/
frame_info = c->frame_pred << 8;
bytestream2_put_le32(&pb, frame_info);
/*
* At least currently Ut Video is IDR only.
* Set flags accordingly.
*/
avctx->coded_frame->key_frame = 1;
avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
pkt->size = bytestream2_tell_p(&pb);
pkt->flags |= AV_PKT_FLAG_KEY;
/* Packet should be done */
*got_packet = 1;
return 0;
}
AVCodec ff_utvideo_encoder = {
.name = "utvideo",
.long_name = NULL_IF_CONFIG_SMALL("Ut Video"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_UTVIDEO,
.priv_data_size = sizeof(UtvideoContext),
.init = utvideo_encode_init,
.encode2 = utvideo_encode_frame,
.close = utvideo_encode_close,
.pix_fmts = (const enum AVPixelFormat[]) {
AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA, AV_PIX_FMT_YUV422P,
AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE
},
};