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FFmpeg/libavcodec/mmaldec.c
Andreas Rheinhardt 4243da4ff4 avcodec/codec_internal: Use union for FFCodec decode/encode callbacks 
This is possible, because every given FFCodec has to implement
exactly one of these. Doing so decreases sizeof(FFCodec) and
therefore decreases the size of the binary.
Notice that in case of position-independent code the decrease
is in .data.rel.ro, so that this translates to decreased
memory consumption.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-04-05 20:02:37 +02:00

856 lines
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/*
* MMAL Video Decoder
* Copyright (c) 2015 rcombs
*
* 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
* MMAL Video Decoder
*/
#include <bcm_host.h>
#include <interface/mmal/mmal.h>
#include <interface/mmal/mmal_parameters_video.h>
#include <interface/mmal/util/mmal_util.h>
#include <interface/mmal/util/mmal_util_params.h>
#include <interface/mmal/util/mmal_default_components.h>
#include <interface/mmal/vc/mmal_vc_api.h>
#include <stdatomic.h>
#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
#include "hwconfig.h"
#include "internal.h"
#include "libavutil/avassert.h"
#include "libavutil/buffer.h"
#include "libavutil/common.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/log.h"
typedef struct FFBufferEntry {
AVBufferRef *ref;
void *data;
size_t length;
int64_t pts, dts;
int flags;
struct FFBufferEntry *next;
} FFBufferEntry;
// MMAL_POOL_T destroys all of its MMAL_BUFFER_HEADER_Ts. If we want correct
// refcounting for AVFrames, we can free the MMAL_POOL_T only after all AVFrames
// have been unreferenced.
typedef struct FFPoolRef {
atomic_int refcount;
MMAL_POOL_T *pool;
} FFPoolRef;
typedef struct FFBufferRef {
MMAL_BUFFER_HEADER_T *buffer;
FFPoolRef *pool;
} FFBufferRef;
typedef struct MMALDecodeContext {
AVClass *av_class;
int extra_buffers;
int extra_decoder_buffers;
MMAL_COMPONENT_T *decoder;
MMAL_QUEUE_T *queue_decoded_frames;
MMAL_POOL_T *pool_in;
FFPoolRef *pool_out;
// Waiting input packets. Because the libavcodec API requires decoding and
// returning packets in lockstep, it can happen that queue_decoded_frames
// contains almost all surfaces - then the decoder input queue can quickly
// fill up and won't accept new input either. Without consuming input, the
// libavcodec API can't return new frames, and we have a logical deadlock.
// This is avoided by queuing such buffers here.
FFBufferEntry *waiting_buffers, *waiting_buffers_tail;
/* Packet used to hold received packets temporarily; not owned by us. */
AVPacket *pkt;
int64_t packets_sent;
atomic_int packets_buffered;
int64_t frames_output;
int eos_received;
int eos_sent;
int extradata_sent;
int interlaced_frame;
int top_field_first;
} MMALDecodeContext;
// Assume decoder is guaranteed to produce output after at least this many
// packets (where each packet contains 1 frame).
#define MAX_DELAYED_FRAMES 16
static void ffmmal_poolref_unref(FFPoolRef *ref)
{
if (ref &&
atomic_fetch_add_explicit(&ref->refcount, -1, memory_order_acq_rel) == 1) {
mmal_pool_destroy(ref->pool);
av_free(ref);
}
}
static void ffmmal_release_frame(void *opaque, uint8_t *data)
{
FFBufferRef *ref = (void *)data;
mmal_buffer_header_release(ref->buffer);
ffmmal_poolref_unref(ref->pool);
av_free(ref);
}
// Setup frame with a new reference to buffer. The buffer must have been
// allocated from the given pool.
static int ffmmal_set_ref(AVFrame *frame, FFPoolRef *pool,
MMAL_BUFFER_HEADER_T *buffer)
{
FFBufferRef *ref = av_mallocz(sizeof(*ref));
if (!ref)
return AVERROR(ENOMEM);
ref->pool = pool;
ref->buffer = buffer;
frame->buf[0] = av_buffer_create((void *)ref, sizeof(*ref),
ffmmal_release_frame, NULL,
AV_BUFFER_FLAG_READONLY);
if (!frame->buf[0]) {
av_free(ref);
return AVERROR(ENOMEM);
}
atomic_fetch_add_explicit(&ref->pool->refcount, 1, memory_order_relaxed);
mmal_buffer_header_acquire(buffer);
frame->format = AV_PIX_FMT_MMAL;
frame->data[3] = (uint8_t *)ref->buffer;
return 0;
}
static void ffmmal_stop_decoder(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_BUFFER_HEADER_T *buffer;
mmal_port_disable(decoder->input[0]);
mmal_port_disable(decoder->output[0]);
mmal_port_disable(decoder->control);
mmal_port_flush(decoder->input[0]);
mmal_port_flush(decoder->output[0]);
mmal_port_flush(decoder->control);
while ((buffer = mmal_queue_get(ctx->queue_decoded_frames)))
mmal_buffer_header_release(buffer);
while (ctx->waiting_buffers) {
FFBufferEntry *buffer = ctx->waiting_buffers;
ctx->waiting_buffers = buffer->next;
if (buffer->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END)
atomic_fetch_add(&ctx->packets_buffered, -1);
av_buffer_unref(&buffer->ref);
av_free(buffer);
}
ctx->waiting_buffers_tail = NULL;
av_assert0(atomic_load(&ctx->packets_buffered) == 0);
ctx->frames_output = ctx->eos_received = ctx->eos_sent = ctx->packets_sent = ctx->extradata_sent = 0;
}
static av_cold int ffmmal_close_decoder(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
if (ctx->decoder)
ffmmal_stop_decoder(avctx);
mmal_component_destroy(ctx->decoder);
ctx->decoder = NULL;
mmal_queue_destroy(ctx->queue_decoded_frames);
mmal_pool_destroy(ctx->pool_in);
ffmmal_poolref_unref(ctx->pool_out);
mmal_vc_deinit();
return 0;
}
static void input_callback(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
{
AVCodecContext *avctx = (AVCodecContext*)port->userdata;
MMALDecodeContext *ctx = avctx->priv_data;
if (!buffer->cmd) {
FFBufferEntry *entry = buffer->user_data;
av_buffer_unref(&entry->ref);
if (entry->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END)
atomic_fetch_add(&ctx->packets_buffered, -1);
av_free(entry);
}
mmal_buffer_header_release(buffer);
}
static void output_callback(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
{
AVCodecContext *avctx = (AVCodecContext*)port->userdata;
MMALDecodeContext *ctx = avctx->priv_data;
mmal_queue_put(ctx->queue_decoded_frames, buffer);
}
static void control_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
{
AVCodecContext *avctx = (AVCodecContext*)port->userdata;
MMAL_STATUS_T status;
if (buffer->cmd == MMAL_EVENT_ERROR) {
status = *(uint32_t *)buffer->data;
av_log(avctx, AV_LOG_ERROR, "MMAL error %d on control port\n", (int)status);
} else {
av_log(avctx, AV_LOG_WARNING, "Unknown MMAL event %s on control port\n",
av_fourcc2str(buffer->cmd));
}
mmal_buffer_header_release(buffer);
}
// Feed free output buffers to the decoder.
static int ffmmal_fill_output_port(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_BUFFER_HEADER_T *buffer;
MMAL_STATUS_T status;
if (!ctx->pool_out)
return AVERROR_UNKNOWN; // format change code failed with OOM previously
while ((buffer = mmal_queue_get(ctx->pool_out->pool->queue))) {
if ((status = mmal_port_send_buffer(ctx->decoder->output[0], buffer))) {
mmal_buffer_header_release(buffer);
av_log(avctx, AV_LOG_ERROR, "MMAL error %d when sending output buffer.\n", (int)status);
return AVERROR_UNKNOWN;
}
}
return 0;
}
static enum AVColorSpace ffmmal_csp_to_av_csp(MMAL_FOURCC_T fourcc)
{
switch (fourcc) {
case MMAL_COLOR_SPACE_BT470_2_BG:
case MMAL_COLOR_SPACE_BT470_2_M:
case MMAL_COLOR_SPACE_ITUR_BT601: return AVCOL_SPC_BT470BG;
case MMAL_COLOR_SPACE_ITUR_BT709: return AVCOL_SPC_BT709;
case MMAL_COLOR_SPACE_FCC: return AVCOL_SPC_FCC;
case MMAL_COLOR_SPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
default: return AVCOL_SPC_UNSPECIFIED;
}
}
static int ffmal_update_format(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_STATUS_T status;
int ret = 0;
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_ES_FORMAT_T *format_out = decoder->output[0]->format;
MMAL_PARAMETER_VIDEO_INTERLACE_TYPE_T interlace_type;
ffmmal_poolref_unref(ctx->pool_out);
if (!(ctx->pool_out = av_mallocz(sizeof(*ctx->pool_out)))) {
ret = AVERROR(ENOMEM);
goto fail;
}
atomic_init(&ctx->pool_out->refcount, 1);
if (!format_out)
goto fail;
if ((status = mmal_port_parameter_set_uint32(decoder->output[0], MMAL_PARAMETER_EXTRA_BUFFERS, ctx->extra_buffers)))
goto fail;
if ((status = mmal_port_parameter_set_boolean(decoder->output[0], MMAL_PARAMETER_VIDEO_INTERPOLATE_TIMESTAMPS, 0)))
goto fail;
if (avctx->pix_fmt == AV_PIX_FMT_MMAL) {
format_out->encoding = MMAL_ENCODING_OPAQUE;
} else {
format_out->encoding_variant = format_out->encoding = MMAL_ENCODING_I420;
}
if ((status = mmal_port_format_commit(decoder->output[0])))
goto fail;
interlace_type.hdr.id = MMAL_PARAMETER_VIDEO_INTERLACE_TYPE;
interlace_type.hdr.size = sizeof(MMAL_PARAMETER_VIDEO_INTERLACE_TYPE_T);
status = mmal_port_parameter_get(decoder->output[0], &interlace_type.hdr);
if (status != MMAL_SUCCESS) {
av_log(avctx, AV_LOG_ERROR, "Cannot read MMAL interlace information!\n");
} else {
ctx->interlaced_frame = (interlace_type.eMode != MMAL_InterlaceProgressive);
ctx->top_field_first = (interlace_type.eMode == MMAL_InterlaceFieldsInterleavedUpperFirst);
}
if ((ret = ff_set_dimensions(avctx, format_out->es->video.crop.x + format_out->es->video.crop.width,
format_out->es->video.crop.y + format_out->es->video.crop.height)) < 0)
goto fail;
if (format_out->es->video.par.num && format_out->es->video.par.den) {
avctx->sample_aspect_ratio.num = format_out->es->video.par.num;
avctx->sample_aspect_ratio.den = format_out->es->video.par.den;
}
if (format_out->es->video.frame_rate.num && format_out->es->video.frame_rate.den) {
avctx->framerate.num = format_out->es->video.frame_rate.num;
avctx->framerate.den = format_out->es->video.frame_rate.den;
}
avctx->colorspace = ffmmal_csp_to_av_csp(format_out->es->video.color_space);
decoder->output[0]->buffer_size =
FFMAX(decoder->output[0]->buffer_size_min, decoder->output[0]->buffer_size_recommended);
decoder->output[0]->buffer_num =
FFMAX(decoder->output[0]->buffer_num_min, decoder->output[0]->buffer_num_recommended) + ctx->extra_buffers;
ctx->pool_out->pool = mmal_pool_create(decoder->output[0]->buffer_num,
decoder->output[0]->buffer_size);
if (!ctx->pool_out->pool) {
ret = AVERROR(ENOMEM);
goto fail;
}
return 0;
fail:
return ret < 0 ? ret : AVERROR_UNKNOWN;
}
static av_cold int ffmmal_init_decoder(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_STATUS_T status;
MMAL_ES_FORMAT_T *format_in;
MMAL_COMPONENT_T *decoder;
int ret = 0;
ctx->pkt = avctx->internal->in_pkt;
bcm_host_init();
if (mmal_vc_init()) {
av_log(avctx, AV_LOG_ERROR, "Cannot initialize MMAL VC driver!\n");
return AVERROR(ENOSYS);
}
if ((ret = ff_get_format(avctx, avctx->codec->pix_fmts)) < 0)
return ret;
avctx->pix_fmt = ret;
if ((status = mmal_component_create(MMAL_COMPONENT_DEFAULT_VIDEO_DECODER, &ctx->decoder)))
goto fail;
decoder = ctx->decoder;
format_in = decoder->input[0]->format;
format_in->type = MMAL_ES_TYPE_VIDEO;
switch (avctx->codec_id) {
case AV_CODEC_ID_MPEG2VIDEO:
format_in->encoding = MMAL_ENCODING_MP2V;
break;
case AV_CODEC_ID_MPEG4:
format_in->encoding = MMAL_ENCODING_MP4V;
break;
case AV_CODEC_ID_VC1:
format_in->encoding = MMAL_ENCODING_WVC1;
break;
case AV_CODEC_ID_H264:
default:
format_in->encoding = MMAL_ENCODING_H264;
break;
}
format_in->es->video.width = FFALIGN(avctx->width, 32);
format_in->es->video.height = FFALIGN(avctx->height, 16);
format_in->es->video.crop.width = avctx->width;
format_in->es->video.crop.height = avctx->height;
format_in->es->video.frame_rate.num = 24000;
format_in->es->video.frame_rate.den = 1001;
format_in->es->video.par.num = avctx->sample_aspect_ratio.num;
format_in->es->video.par.den = avctx->sample_aspect_ratio.den;
format_in->flags = MMAL_ES_FORMAT_FLAG_FRAMED;
av_log(avctx, AV_LOG_DEBUG, "Using MMAL %s encoding.\n",
av_fourcc2str(format_in->encoding));
#if HAVE_MMAL_PARAMETER_VIDEO_MAX_NUM_CALLBACKS
if (mmal_port_parameter_set_uint32(decoder->input[0], MMAL_PARAMETER_VIDEO_MAX_NUM_CALLBACKS,
-1 - ctx->extra_decoder_buffers)) {
av_log(avctx, AV_LOG_WARNING, "Could not set input buffering limit.\n");
}
#endif
if ((status = mmal_port_format_commit(decoder->input[0])))
goto fail;
decoder->input[0]->buffer_num =
FFMAX(decoder->input[0]->buffer_num_min, 20);
decoder->input[0]->buffer_size =
FFMAX(decoder->input[0]->buffer_size_min, 512 * 1024);
ctx->pool_in = mmal_pool_create(decoder->input[0]->buffer_num, 0);
if (!ctx->pool_in) {
ret = AVERROR(ENOMEM);
goto fail;
}
if ((ret = ffmal_update_format(avctx)) < 0)
goto fail;
ctx->queue_decoded_frames = mmal_queue_create();
if (!ctx->queue_decoded_frames)
goto fail;
decoder->input[0]->userdata = (void*)avctx;
decoder->output[0]->userdata = (void*)avctx;
decoder->control->userdata = (void*)avctx;
if ((status = mmal_port_enable(decoder->control, control_port_cb)))
goto fail;
if ((status = mmal_port_enable(decoder->input[0], input_callback)))
goto fail;
if ((status = mmal_port_enable(decoder->output[0], output_callback)))
goto fail;
if ((status = mmal_component_enable(decoder)))
goto fail;
return 0;
fail:
ffmmal_close_decoder(avctx);
return ret < 0 ? ret : AVERROR_UNKNOWN;
}
static void ffmmal_flush(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_STATUS_T status;
ffmmal_stop_decoder(avctx);
if ((status = mmal_port_enable(decoder->control, control_port_cb)))
goto fail;
if ((status = mmal_port_enable(decoder->input[0], input_callback)))
goto fail;
if ((status = mmal_port_enable(decoder->output[0], output_callback)))
goto fail;
return;
fail:
av_log(avctx, AV_LOG_ERROR, "MMAL flush error: %i\n", (int)status);
}
// Split packets and add them to the waiting_buffers list. We don't queue them
// immediately, because it can happen that the decoder is temporarily blocked
// (due to us not reading/returning enough output buffers) and won't accept
// new input. (This wouldn't be an issue if MMAL input buffers always were
// complete frames - then the input buffer just would have to be big enough.)
// If is_extradata is set, send it as MMAL_BUFFER_HEADER_FLAG_CONFIG.
static int ffmmal_add_packet(AVCodecContext *avctx, AVPacket *avpkt,
int is_extradata)
{
MMALDecodeContext *ctx = avctx->priv_data;
const AVBufferRef *buf = NULL;
int size = 0;
uint8_t *data = (uint8_t *)"";
uint8_t *start;
int ret = 0;
if (avpkt->size) {
ret = av_packet_make_refcounted(avpkt);
if (ret < 0)
goto done;
buf = avpkt->buf;
data = avpkt->data;
size = avpkt->size;
if (!is_extradata)
ctx->packets_sent++;
} else {
if (ctx->eos_sent)
goto done;
if (!ctx->packets_sent) {
// Short-cut the flush logic to avoid upsetting MMAL.
ctx->eos_sent = 1;
ctx->eos_received = 1;
goto done;
}
}
start = data;
do {
FFBufferEntry *buffer = av_mallocz(sizeof(*buffer));
if (!buffer) {
ret = AVERROR(ENOMEM);
goto done;
}
buffer->data = data;
buffer->length = FFMIN(size, ctx->decoder->input[0]->buffer_size);
if (is_extradata)
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_CONFIG;
if (data == start)
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_FRAME_START;
data += buffer->length;
size -= buffer->length;
buffer->pts = avpkt->pts == AV_NOPTS_VALUE ? MMAL_TIME_UNKNOWN : avpkt->pts;
buffer->dts = avpkt->dts == AV_NOPTS_VALUE ? MMAL_TIME_UNKNOWN : avpkt->dts;
if (!size) {
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_FRAME_END;
atomic_fetch_add(&ctx->packets_buffered, 1);
}
if (!buffer->length) {
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_EOS;
ctx->eos_sent = 1;
}
if (buf) {
buffer->ref = av_buffer_ref(buf);
if (!buffer->ref) {
av_free(buffer);
ret = AVERROR(ENOMEM);
goto done;
}
}
// Insert at end of the list
if (!ctx->waiting_buffers)
ctx->waiting_buffers = buffer;
if (ctx->waiting_buffers_tail)
ctx->waiting_buffers_tail->next = buffer;
ctx->waiting_buffers_tail = buffer;
} while (size);
done:
av_packet_unref(avpkt);
return ret;
}
// Move prepared/split packets from waiting_buffers to the MMAL decoder.
static int ffmmal_fill_input_port(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
while (ctx->waiting_buffers) {
MMAL_BUFFER_HEADER_T *mbuffer;
FFBufferEntry *buffer;
MMAL_STATUS_T status;
mbuffer = mmal_queue_get(ctx->pool_in->queue);
if (!mbuffer)
return 0;
buffer = ctx->waiting_buffers;
mmal_buffer_header_reset(mbuffer);
mbuffer->cmd = 0;
mbuffer->pts = buffer->pts;
mbuffer->dts = buffer->dts;
mbuffer->flags = buffer->flags;
mbuffer->data = buffer->data;
mbuffer->length = buffer->length;
mbuffer->user_data = buffer;
mbuffer->alloc_size = ctx->decoder->input[0]->buffer_size;
// Remove from start of the list
ctx->waiting_buffers = buffer->next;
if (ctx->waiting_buffers_tail == buffer)
ctx->waiting_buffers_tail = NULL;
if ((status = mmal_port_send_buffer(ctx->decoder->input[0], mbuffer))) {
mmal_buffer_header_release(mbuffer);
av_buffer_unref(&buffer->ref);
if (buffer->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END)
atomic_fetch_add(&ctx->packets_buffered, -1);
av_free(buffer);
}
if (status) {
av_log(avctx, AV_LOG_ERROR, "MMAL error %d when sending input\n", (int)status);
return AVERROR_UNKNOWN;
}
}
return 0;
}
static int ffmal_copy_frame(AVCodecContext *avctx, AVFrame *frame,
MMAL_BUFFER_HEADER_T *buffer)
{
MMALDecodeContext *ctx = avctx->priv_data;
int ret = 0;
frame->interlaced_frame = ctx->interlaced_frame;
frame->top_field_first = ctx->top_field_first;
if (avctx->pix_fmt == AV_PIX_FMT_MMAL) {
if (!ctx->pool_out)
return AVERROR_UNKNOWN; // format change code failed with OOM previously
if ((ret = ff_decode_frame_props(avctx, frame)) < 0)
goto done;
if ((ret = ffmmal_set_ref(frame, ctx->pool_out, buffer)) < 0)
goto done;
} else {
int w = FFALIGN(avctx->width, 32);
int h = FFALIGN(avctx->height, 16);
uint8_t *src[4];
int linesize[4];
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
goto done;
av_image_fill_arrays(src, linesize,
buffer->data + buffer->type->video.offset[0],
avctx->pix_fmt, w, h, 1);
av_image_copy(frame->data, frame->linesize, (const uint8_t **)src, linesize,
avctx->pix_fmt, avctx->width, avctx->height);
}
frame->sample_aspect_ratio = avctx->sample_aspect_ratio;
frame->width = avctx->width;
frame->width = avctx->width;
frame->height = avctx->height;
frame->format = avctx->pix_fmt;
frame->pts = buffer->pts == MMAL_TIME_UNKNOWN ? AV_NOPTS_VALUE : buffer->pts;
frame->pkt_dts = AV_NOPTS_VALUE;
done:
return ret;
}
// Fetch a decoded buffer and place it into the frame parameter.
static int ffmmal_read_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_BUFFER_HEADER_T *buffer = NULL;
MMAL_STATUS_T status = 0;
int ret = 0;
if (ctx->eos_received)
goto done;
while (1) {
// To ensure decoding in lockstep with a constant delay between fed packets
// and output frames, we always wait until an output buffer is available.
// Except during start we don't know after how many input packets the decoder
// is going to return the first buffer, and we can't distinguish decoder
// being busy from decoder waiting for input. So just poll at the start and
// keep feeding new data to the buffer.
// We are pretty sure the decoder will produce output if we sent more input
// frames than what a H.264 decoder could logically delay. This avoids too
// excessive buffering.
// We also wait if we sent eos, but didn't receive it yet (think of decoding
// stream with a very low number of frames).
if (atomic_load(&ctx->packets_buffered) > MAX_DELAYED_FRAMES ||
(ctx->packets_sent && ctx->eos_sent)) {
// MMAL will ignore broken input packets, which means the frame we
// expect here may never arrive. Dealing with this correctly is
// complicated, so here's a hack to avoid that it freezes forever
// in this unlikely situation.
buffer = mmal_queue_timedwait(ctx->queue_decoded_frames, 100);
if (!buffer) {
av_log(avctx, AV_LOG_ERROR, "Did not get output frame from MMAL.\n");
ret = AVERROR_UNKNOWN;
goto done;
}
} else {
buffer = mmal_queue_get(ctx->queue_decoded_frames);
if (!buffer)
goto done;
}
ctx->eos_received |= !!(buffer->flags & MMAL_BUFFER_HEADER_FLAG_EOS);
if (ctx->eos_received)
goto done;
if (buffer->cmd == MMAL_EVENT_FORMAT_CHANGED) {
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_EVENT_FORMAT_CHANGED_T *ev = mmal_event_format_changed_get(buffer);
MMAL_BUFFER_HEADER_T *stale_buffer;
av_log(avctx, AV_LOG_INFO, "Changing output format.\n");
if ((status = mmal_port_disable(decoder->output[0])))
goto done;
while ((stale_buffer = mmal_queue_get(ctx->queue_decoded_frames)))
mmal_buffer_header_release(stale_buffer);
mmal_format_copy(decoder->output[0]->format, ev->format);
if ((ret = ffmal_update_format(avctx)) < 0)
goto done;
if ((status = mmal_port_enable(decoder->output[0], output_callback)))
goto done;
if ((ret = ffmmal_fill_output_port(avctx)) < 0)
goto done;
if ((ret = ffmmal_fill_input_port(avctx)) < 0)
goto done;
mmal_buffer_header_release(buffer);
continue;
} else if (buffer->cmd) {
av_log(avctx, AV_LOG_WARNING, "Unknown MMAL event %s on output port\n",
av_fourcc2str(buffer->cmd));
goto done;
} else if (buffer->length == 0) {
// Unused output buffer that got drained after format change.
mmal_buffer_header_release(buffer);
continue;
}
ctx->frames_output++;
if ((ret = ffmal_copy_frame(avctx, frame, buffer)) < 0)
goto done;
*got_frame = 1;
break;
}
done:
if (buffer)
mmal_buffer_header_release(buffer);
if (status && ret >= 0)
ret = AVERROR_UNKNOWN;
return ret;
}
static int ffmmal_receive_frame(AVCodecContext *avctx, AVFrame *frame)
{
MMALDecodeContext *ctx = avctx->priv_data;
AVPacket *const avpkt = ctx->pkt;
int ret = 0;
int got_frame = 0;
if (avctx->extradata_size && !ctx->extradata_sent) {
avpkt->data = avctx->extradata;
avpkt->size = avctx->extradata_size;
ctx->extradata_sent = 1;
if ((ret = ffmmal_add_packet(avctx, avpkt, 1)) < 0)
return ret;
}
ret = ff_decode_get_packet(avctx, avpkt);
if (ret == 0) {
if ((ret = ffmmal_add_packet(avctx, avpkt, 0)) < 0)
return ret;
} else if (ret < 0 && !(ret == AVERROR(EAGAIN)))
return ret;
if ((ret = ffmmal_fill_input_port(avctx)) < 0)
return ret;
if ((ret = ffmmal_fill_output_port(avctx)) < 0)
return ret;
if ((ret = ffmmal_read_frame(avctx, frame, &got_frame)) < 0)
return ret;
// ffmmal_read_frame() can block for a while. Since the decoder is
// asynchronous, it's a good idea to fill the ports again.
if ((ret = ffmmal_fill_output_port(avctx)) < 0)
return ret;
if ((ret = ffmmal_fill_input_port(avctx)) < 0)
return ret;
if (!got_frame && ret == 0)
return AVERROR(EAGAIN);
else
return ret;
}
static const AVCodecHWConfigInternal *const mmal_hw_configs[] = {
HW_CONFIG_INTERNAL(MMAL),
NULL
};
static const AVOption options[]={
{"extra_buffers", "extra buffers", offsetof(MMALDecodeContext, extra_buffers), AV_OPT_TYPE_INT, {.i64 = 10}, 0, 256, 0},
{"extra_decoder_buffers", "extra MMAL internal buffered frames", offsetof(MMALDecodeContext, extra_decoder_buffers), AV_OPT_TYPE_INT, {.i64 = 10}, 0, 256, 0},
{NULL}
};
static const AVClass ffmmal_dec_class = {
.class_name = "mmal_dec",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
#define FFMMAL_DEC(NAME, ID) \
const FFCodec ff_##NAME##_mmal_decoder = { \
.p.name = #NAME "_mmal", \
.p.long_name = NULL_IF_CONFIG_SMALL(#NAME " (mmal)"), \
.p.type = AVMEDIA_TYPE_VIDEO, \
.p.id = ID, \
.priv_data_size = sizeof(MMALDecodeContext), \
.init = ffmmal_init_decoder, \
.close = ffmmal_close_decoder, \
FF_CODEC_RECEIVE_FRAME_CB(ffmmal_receive_frame), \
.flush = ffmmal_flush, \
.p.priv_class = &ffmmal_dec_class, \
.p.capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_HARDWARE, \
.caps_internal = FF_CODEC_CAP_SETS_PKT_DTS, \
.p.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_MMAL, \
AV_PIX_FMT_YUV420P, \
AV_PIX_FMT_NONE}, \
.hw_configs = mmal_hw_configs, \
.p.wrapper_name = "mmal", \
};
FFMMAL_DEC(h264, AV_CODEC_ID_H264)
FFMMAL_DEC(mpeg2, AV_CODEC_ID_MPEG2VIDEO)
FFMMAL_DEC(mpeg4, AV_CODEC_ID_MPEG4)
FFMMAL_DEC(vc1, AV_CODEC_ID_VC1)
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