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FFmpeg/libavcodec/libtheoraenc.c
Andreas Rheinhardt 6ba55e9652 avcodec/libtheoraenc: Avoid copying data, allow user-supplied buffers
Here the packet size is known before allocating the packet because
the encoder provides said information (and works with internal buffers
itself), so one can use this information to avoid the implicit use of
another intermediate buffer for the packet data; and by switching to
ff_get_encode_buffer() one can also allow user-supplied buffers.

Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2021-05-23 14:47:49 +02:00

386 lines
13 KiB
C

/*
* Copyright (c) 2006 Paul Richards <paul.richards@gmail.com>
*
* 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
* @brief Theora encoder using libtheora.
* @author Paul Richards <paul.richards@gmail.com>
*
* A lot of this is copy / paste from other output codecs in
* libavcodec or pure guesswork (or both).
*
* I have used t_ prefixes on variables which are libtheora types
* and o_ prefixes on variables which are libogg types.
*/
/* FFmpeg includes */
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/pixdesc.h"
#include "libavutil/log.h"
#include "libavutil/base64.h"
#include "avcodec.h"
#include "encode.h"
#include "internal.h"
/* libtheora includes */
#include <theora/theoraenc.h>
typedef struct TheoraContext {
th_enc_ctx *t_state;
uint8_t *stats;
int stats_size;
int stats_offset;
int uv_hshift;
int uv_vshift;
int keyframe_mask;
} TheoraContext;
/** Concatenate an ogg_packet into the extradata. */
static int concatenate_packet(unsigned int* offset,
AVCodecContext* avc_context,
const ogg_packet* packet)
{
const char* message = NULL;
int newsize = avc_context->extradata_size + 2 + packet->bytes;
int err = AVERROR_INVALIDDATA;
if (packet->bytes < 0) {
message = "ogg_packet has negative size";
} else if (packet->bytes > 0xffff) {
message = "ogg_packet is larger than 65535 bytes";
} else if (newsize < avc_context->extradata_size) {
message = "extradata_size would overflow";
} else {
if ((err = av_reallocp(&avc_context->extradata, newsize)) < 0) {
avc_context->extradata_size = 0;
message = "av_realloc failed";
}
}
if (message) {
av_log(avc_context, AV_LOG_ERROR, "concatenate_packet failed: %s\n", message);
return err;
}
avc_context->extradata_size = newsize;
AV_WB16(avc_context->extradata + (*offset), packet->bytes);
*offset += 2;
memcpy(avc_context->extradata + (*offset), packet->packet, packet->bytes);
(*offset) += packet->bytes;
return 0;
}
static int get_stats(AVCodecContext *avctx, int eos)
{
#ifdef TH_ENCCTL_2PASS_OUT
TheoraContext *h = avctx->priv_data;
uint8_t *buf;
int bytes;
bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_OUT, &buf, sizeof(buf));
if (bytes < 0) {
av_log(avctx, AV_LOG_ERROR, "Error getting first pass stats\n");
return AVERROR_EXTERNAL;
}
if (!eos) {
void *tmp = av_fast_realloc(h->stats, &h->stats_size,
h->stats_offset + bytes);
if (!tmp)
return AVERROR(ENOMEM);
h->stats = tmp;
memcpy(h->stats + h->stats_offset, buf, bytes);
h->stats_offset += bytes;
} else {
int b64_size = AV_BASE64_SIZE(h->stats_offset);
// libtheora generates a summary header at the end
memcpy(h->stats, buf, bytes);
avctx->stats_out = av_malloc(b64_size);
if (!avctx->stats_out)
return AVERROR(ENOMEM);
av_base64_encode(avctx->stats_out, b64_size, h->stats, h->stats_offset);
}
return 0;
#else
av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
return AVERROR(ENOSUP);
#endif
}
// libtheora won't read the entire buffer we give it at once, so we have to
// repeatedly submit it...
static int submit_stats(AVCodecContext *avctx)
{
#ifdef TH_ENCCTL_2PASS_IN
TheoraContext *h = avctx->priv_data;
int bytes;
if (!h->stats) {
if (!avctx->stats_in) {
av_log(avctx, AV_LOG_ERROR, "No statsfile for second pass\n");
return AVERROR(EINVAL);
}
h->stats_size = strlen(avctx->stats_in) * 3/4;
h->stats = av_malloc(h->stats_size);
if (!h->stats) {
h->stats_size = 0;
return AVERROR(ENOMEM);
}
h->stats_size = av_base64_decode(h->stats, avctx->stats_in, h->stats_size);
}
while (h->stats_size - h->stats_offset > 0) {
bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_IN,
h->stats + h->stats_offset,
h->stats_size - h->stats_offset);
if (bytes < 0) {
av_log(avctx, AV_LOG_ERROR, "Error submitting stats\n");
return AVERROR_EXTERNAL;
}
if (!bytes)
return 0;
h->stats_offset += bytes;
}
return 0;
#else
av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
return AVERROR(ENOSUP);
#endif
}
static av_cold int encode_init(AVCodecContext* avc_context)
{
th_info t_info;
th_comment t_comment;
ogg_packet o_packet;
unsigned int offset;
TheoraContext *h = avc_context->priv_data;
uint32_t gop_size = avc_context->gop_size;
int ret;
/* Set up the theora_info struct */
th_info_init(&t_info);
t_info.frame_width = FFALIGN(avc_context->width, 16);
t_info.frame_height = FFALIGN(avc_context->height, 16);
t_info.pic_width = avc_context->width;
t_info.pic_height = avc_context->height;
t_info.pic_x = 0;
t_info.pic_y = 0;
/* Swap numerator and denominator as time_base in AVCodecContext gives the
* time period between frames, but theora_info needs the framerate. */
t_info.fps_numerator = avc_context->time_base.den;
t_info.fps_denominator = avc_context->time_base.num;
if (avc_context->sample_aspect_ratio.num) {
t_info.aspect_numerator = avc_context->sample_aspect_ratio.num;
t_info.aspect_denominator = avc_context->sample_aspect_ratio.den;
} else {
t_info.aspect_numerator = 1;
t_info.aspect_denominator = 1;
}
if (avc_context->color_primaries == AVCOL_PRI_BT470M)
t_info.colorspace = TH_CS_ITU_REC_470M;
else if (avc_context->color_primaries == AVCOL_PRI_BT470BG)
t_info.colorspace = TH_CS_ITU_REC_470BG;
else
t_info.colorspace = TH_CS_UNSPECIFIED;
if (avc_context->pix_fmt == AV_PIX_FMT_YUV420P)
t_info.pixel_fmt = TH_PF_420;
else if (avc_context->pix_fmt == AV_PIX_FMT_YUV422P)
t_info.pixel_fmt = TH_PF_422;
else if (avc_context->pix_fmt == AV_PIX_FMT_YUV444P)
t_info.pixel_fmt = TH_PF_444;
else {
av_log(avc_context, AV_LOG_ERROR, "Unsupported pix_fmt\n");
return AVERROR(EINVAL);
}
ret = av_pix_fmt_get_chroma_sub_sample(avc_context->pix_fmt, &h->uv_hshift, &h->uv_vshift);
if (ret)
return ret;
if (avc_context->flags & AV_CODEC_FLAG_QSCALE) {
/* Clip global_quality in QP units to the [0 - 10] range
to be consistent with the libvorbis implementation.
Theora accepts a quality parameter which is an int value in
the [0 - 63] range.
*/
t_info.quality = av_clipf(avc_context->global_quality / (float)FF_QP2LAMBDA, 0, 10) * 6.3;
t_info.target_bitrate = 0;
} else {
t_info.target_bitrate = avc_context->bit_rate;
t_info.quality = 0;
}
/* Now initialise libtheora */
h->t_state = th_encode_alloc(&t_info);
if (!h->t_state) {
av_log(avc_context, AV_LOG_ERROR, "theora_encode_init failed\n");
return AVERROR_EXTERNAL;
}
h->keyframe_mask = (1 << t_info.keyframe_granule_shift) - 1;
/* Clear up theora_info struct */
th_info_clear(&t_info);
if (th_encode_ctl(h->t_state, TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE,
&gop_size, sizeof(gop_size))) {
av_log(avc_context, AV_LOG_ERROR, "Error setting GOP size\n");
return AVERROR_EXTERNAL;
}
// need to enable 2 pass (via TH_ENCCTL_2PASS_) before encoding headers
if (avc_context->flags & AV_CODEC_FLAG_PASS1) {
if ((ret = get_stats(avc_context, 0)) < 0)
return ret;
} else if (avc_context->flags & AV_CODEC_FLAG_PASS2) {
if ((ret = submit_stats(avc_context)) < 0)
return ret;
}
/*
Output first header packet consisting of theora
header, comment, and tables.
Each one is prefixed with a 16-bit size, then they
are concatenated together into libavcodec's extradata.
*/
offset = 0;
/* Headers */
th_comment_init(&t_comment);
while (th_encode_flushheader(h->t_state, &t_comment, &o_packet))
if ((ret = concatenate_packet(&offset, avc_context, &o_packet)) < 0)
return ret;
th_comment_clear(&t_comment);
return 0;
}
static int encode_frame(AVCodecContext* avc_context, AVPacket *pkt,
const AVFrame *frame, int *got_packet)
{
th_ycbcr_buffer t_yuv_buffer;
TheoraContext *h = avc_context->priv_data;
ogg_packet o_packet;
int result, i, ret;
// EOS, finish and get 1st pass stats if applicable
if (!frame) {
th_encode_packetout(h->t_state, 1, &o_packet);
if (avc_context->flags & AV_CODEC_FLAG_PASS1)
if ((ret = get_stats(avc_context, 1)) < 0)
return ret;
return 0;
}
/* Copy planes to the theora yuv_buffer */
for (i = 0; i < 3; i++) {
t_yuv_buffer[i].width = FFALIGN(avc_context->width, 16) >> (i && h->uv_hshift);
t_yuv_buffer[i].height = FFALIGN(avc_context->height, 16) >> (i && h->uv_vshift);
t_yuv_buffer[i].stride = frame->linesize[i];
t_yuv_buffer[i].data = frame->data[i];
}
if (avc_context->flags & AV_CODEC_FLAG_PASS2)
if ((ret = submit_stats(avc_context)) < 0)
return ret;
/* Now call into theora_encode_YUVin */
result = th_encode_ycbcr_in(h->t_state, t_yuv_buffer);
if (result) {
const char* message;
switch (result) {
case -1:
message = "differing frame sizes";
break;
case TH_EINVAL:
message = "encoder is not ready or is finished";
break;
default:
message = "unknown reason";
break;
}
av_log(avc_context, AV_LOG_ERROR, "theora_encode_YUVin failed (%s) [%d]\n", message, result);
return AVERROR_EXTERNAL;
}
if (avc_context->flags & AV_CODEC_FLAG_PASS1)
if ((ret = get_stats(avc_context, 0)) < 0)
return ret;
/* Pick up returned ogg_packet */
result = th_encode_packetout(h->t_state, 0, &o_packet);
switch (result) {
case 0:
/* No packet is ready */
return 0;
case 1:
/* Success, we have a packet */
break;
default:
av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed [%d]\n", result);
return AVERROR_EXTERNAL;
}
/* Copy ogg_packet content out to buffer */
if ((ret = ff_get_encode_buffer(avc_context, pkt, o_packet.bytes, 0)) < 0)
return ret;
memcpy(pkt->data, o_packet.packet, o_packet.bytes);
// HACK: assumes no encoder delay, this is true until libtheora becomes
// multithreaded (which will be disabled unless explicitly requested)
pkt->pts = pkt->dts = frame->pts;
if (!(o_packet.granulepos & h->keyframe_mask))
pkt->flags |= AV_PKT_FLAG_KEY;
*got_packet = 1;
return 0;
}
static av_cold int encode_close(AVCodecContext* avc_context)
{
TheoraContext *h = avc_context->priv_data;
th_encode_free(h->t_state);
av_freep(&h->stats);
av_freep(&avc_context->stats_out);
avc_context->extradata_size = 0;
return 0;
}
/** AVCodec struct exposed to libavcodec */
const AVCodec ff_libtheora_encoder = {
.name = "libtheora",
.long_name = NULL_IF_CONFIG_SMALL("libtheora Theora"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_THEORA,
.capabilities = AV_CODEC_CAP_DR1 |
AV_CODEC_CAP_DELAY /* for statsfile summary */,
.priv_data_size = sizeof(TheoraContext),
.init = encode_init,
.close = encode_close,
.encode2 = encode_frame,
.pix_fmts = (const enum AVPixelFormat[]){
AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_NONE
},
.wrapper_name = "libtheora",
};